A catalyst is a stable object (usually a still life ) which can interact with an active region and later return to its original state. Catalysts are very useful in conduits and in many other applications. Here is an example of a stable catalyst:
x=11, y = 10, rule = LifeHistory
2.C$2.C$.2C6.2A$4.2A.A2.A$3.A.A.3A$A2.A.A$4A.3A$4.A3.A$2.A.A2.2A$2.2A
!
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The green still life interacts with the white object, and recovers to its original state by generation 15. In this tutorial, you'll learn the main types of catalyses and their applications. But first, we need to cover some important definitions:
Important terms Stable catalyst : a catalyst which is a still life. Most catalyses are of this form. In this tutorial we will only focus on stable catalyses, as periodic catalyses are as of now quite underdeveloped.Periodic catalyst : a catalyst which is an oscillator . These are generally considered inferior to stable catalyses because they usually only work in a fraction of the generations as a stable catalyst, since they usually only work in one phase of the periodic catalyst.Transparent catalyst or transparent object : an object which is destroyed completely (all of its cells being off at the same time) then restored (in the same position and with the same orientation)Pseudo-transparent catalyst : a catalyst that loses all of its cells but not at the same time (i.e. for each generation, at least one of its cells is alive)Recovery time : the time it takes for a catalyst to return back to its state before interacting. In the example above, the recovery time is 15.Replacement catalyst : When a common catalyst fails, another, less common, catalyst must be used.Rock : A catalyst which does not lose any of its cells, even temporarily, during the interaction process. The snake-type catalyses below are examples of rocks.Let's explore the different types of catalysts now!
Types of common catalyses Fishhook (eater 1)
Here are some examples of fishhook catalyses:
x=28, y = 7, rule = LifeHistory
2.A8.2A7.A.A$A.C8.AC9.C$.AC8.AC7.2AC$4.2A8.2A8.2A$4.A.A7.A.A7.A.A$6.A
9.A9.A$6.2A8.2A8.2A!
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The marked white cells should always be on in a fishhook-type catalyst. Sometimes, the fishhook may engage in a more unusual manner, but these are rarer:
x=21, y = 6, rule = B3/S23
o3b2o8b2o$2ob2o8b2o$3bo3b2o4bo3b2o$7bobo7bobo$9bo9bo$9b2o8b2o!
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In the left example, the fishhook later catalyses a blinker. This catalysis is often useful.
Even rarer is when the tail of the fishhook is to be used as a rock (the red cells must not be born):
x=22, y = 7, rule = LifeHistory
6.2A12.2A$7.A13.A$4.3A11.3A$3.DA12.DA$4.D13.D$.3C11.3C$A3.2A8.A2.2A!
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Recognizing when to use a fishhook catalysis is really a matter of experience. For practice, try placing an eater 1 somewhere within this blue field to eat the middleweight spaceship (click on the thumbnail below to draw cells in LifeViewer using the pencil icon):
x=18, y = 9, rule = LifeHistory
.5A$A4.A$5.A4.8B$A3.A5.8B$2.A7.8B$10.8B$10.8B$10.8B$10.8B!
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Block
Here are some examples of block catalyses:
x=18, y = 7, rule = LifeHistory
.A14.A$A.A5.3A6.A$A.A5.3A3.A.A$.C7.C5.C2$.2A5.2A4.2A$.2A5.2A4.2A!
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Block catalyses typically occur when there is a one cell leading edge of a pattern, shown in white above.
They are usually much easier to recognize than fishhook-type catalyses, however they may sometimes fail:
x=12, y = 6, rule = B3/S23
10b2o$ob2o5b2o$bo7bo2$b2o6b2o$b2o6b2o!
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Moving the block over by one cell often fixes this problem:
x=12, y = 6, rule = B3/S23
10b2o$ob2o5b2o$bo7bo2$2o6b2o$2o6b2o!
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As practice, try to eat this bun with a block placed in the blue region:
x=12, y = 6, rule = LifeHistory
6B$6B$6B2.3A$6B2.A2.A$6B3.2A$6B!
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Boat Boat catalyses are rarer, but are still useful. Here are two examples:
x=22, y = 10, rule = LifeHistory
16.A$16.2A$15.2A2$.2A$2CB16.2DB2$.A18.A$A.A16.A.A$2A17.2A!
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They typically occur when there is a two cell leading edge, which is marked. Boat catalyses fail very often, so see the "Replacement catalysts" section below for potential replacement catalysts. As a general rule, boats are most likely to succeed when a cell adjacent to the leading edge (shown in blue) will turn on in the following generation.
There is a secondary boat catalysis that works on objects with a line of three or more cells, but it's important here that the red cell does not turn on:
x=22, y = 6, rule = LifeHistory
3.A3.A10.A$6.A$2.D3C11.D4C$.A14.A$A.A12.A.A$2A13.2A!
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The boat also has a tertiary catalysis:
x=8, y = 7, rule = B3/S23
b2o$obo$bo$4bo$2b2obo$2b2obo$3bo3bo!
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Snake Snake catalyses are examples of rocks, or catalysts which do not change even temporarily when interacting with an object. They must function this way due to the fact that the two cells in the center would die from overpopulation due to already having three live neighbors.
Three example snake catalysts are shown below. The white cells should always be on to trigger the important next generation, where the snake functions as a rock:
x=24, y = 9, rule = LifeHistory
15.A6.A$4.A8.2A8.A$2A.2A6.2A7.A.2A$.C9.C9.C2$2.2A8.2A8.2A$3.A9.A9.A$
2.A9.A9.A$2.2A8.2A8.2A!
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Both the head and tail of a fishhook can function as a snake catalyst:
x=26, y = 8, rule = LifeHistory
A9.A9.A$.A.3A5.A.3A5.A.3A$2.C9.C9.C2$3.2A8.2A8.2A$4.A9.A9.A$3.A10.A.A
4.3A$3.2A10.2A4.A!
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Conduit 1 is an example of a conduit using a snake catalyst. Try to catalyze the reaction below with a snake in the blue field (as a hint, the cell which should trigger the rock interaction is marked):
x=15, y = 7, rule = LifeHistory
7B$7B4.2A.A$7B5.3A$7B6.A$7BD$7B4.2A$7B4.2A!
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Tub Tub catalyses can be tricky to find, but they are most likely to work when the frontend of the active region is two or three cells long, like one of the examples below:
x=39, y = 73, rule = LifeHistory
25.A12.A$4.A5.A10.A3.A$3A5.A.A15.A7.A.2A$3A5.3A7.3A6.2A6.2A2$2.A7.A7.
A7.A7.A$.A.A5.A.A5.A.A5.A.A5.A.A$2.A7.A7.A7.A7.A4$17.A2$17.A2$14.A2.A
2.A2$15.A.A.A2$17.A3$.A7.A15.2A10.A$A.2A4.A.2A7.2A5.2A8.2A$A.A5.A.A8.
A7.A7.3A$2.C7.C7.C8.C7.C$2.A7.A7.A7.A7.A$.A.A5.A.A5.A.A5.A.A5.A.A$2.A
7.A7.A7.A7.A4$17.A2$17.A2$14.A2.A2.A2$15.A.A.A2$17.A3$.2A6.2A14.3A8.
2A$A.2A4.A.2A7.2A4.A.A7.A2.A$2.A7.A7.3A6.2A6.A.A$2.2C6.2C6.2C6.2C6.2C
$.2AC5.2AC5.2AC6.AC6.AC$.A.A5.A.A5.A.A5.A.A5.A.A$2.A7.A7.A7.A7.A4$17.
A2$17.A2$14.A2.A2.A2$15.A.A.A2$17.A4$26.A$.3A5.3A13.A.A8.2A$3.A7.A6.A
.A4.A9.A2.A$28.A6.A2$.A2.A4.A2.A4.A2.A4.A2.A4.A2.A$.A.A5.A.A5.A.A5.A.
A5.A.A$2.A7.A7.A7.A7.A!
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The reactions start differently but end up the same way through the same general mechanism:
On generation 1, one cell (marked in white) is born next to the tub;
On generation 2, two more cells are born next to the tub. This causes the three white cells to die;
By generation 3, the cells in the center have died and what remains is a 5-cell parent of the tub. In all tub catalyses, the tub should turn into this 5-cell parent. Ship Observe the following reaction:
x=7, y = 9, rule = B3/S23
bo$o$2o$2b3o3$4b2o$4bobo$5b2o!
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The ship is turned into a relative of the I-heptomino (specifically a great-uncle) then is turned back into a ship by a perfectly-timed temporary induction. The ship rarely recovers by its own, but it's worth trying because it has replacement catalysts that recover much more often.
Replacement catalyses So, you've tried to catalyze a reaction, but the common catalyst fails! Luckily for you, this is not a complete disaster, since many replacement catalysts exist exactly to assist you when your fishhook or block doesn't just work out.
Fishhook replacements The most common way for a fishhook to fail is something like this:
x=8, y = 8, rule = B3/S23
o$o2bo$b3o2$4b2o$4bobo$6bo$6b2o!
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Luckily, this is also the easiest to fix. Simply flip the eater 1 around and it works!
x=32, y = 9, rule = B3/S23
o15bo$o2bo20bo$b3o14bo5bo2bo$25b3o$4b2o4bobobobobobo$4bobo21b2o$6bo11b
o9bo$6b2o21b3o$16bo14bo!
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This was a bit cheating, however. Sometimes, we need a genuinely new catalyst. Here are two almost-catalyses where the fishhook almost recovers, but an extra spark destroys it or an extra cell gets attached to its recovering phase:
x=20, y = 8, rule = B3/S23
12bo$o10bobo$b2o10b2o$2o12bo$4b2o7bo2b2o$4bobo9bobo$6bo11bo$6b2o10b2o!
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The most common replacement catalyst for a fishhook is the handy eater 2 . An eater 2 recovers differently from an eater 1, making it more versatile (and its symmetry means that it can eat from two directions). It can handle both of our problems:
x=23, y = 11, rule = B3/S23
12bo$o10bobo$b2o10b2o$2o12bo$4b2obo5bo2b2obo$4b2ob3o6b2ob3o$10bo11bo$
4b2ob3o6b2ob3o$5bobo9bobo$5bobo9bobo$6bo11bo!
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There are many, many more cases in which neither an eater 1 nor an eater 2 works. This guide, by Entity Valkyrie and MathAndCode, addresses many of these:
x=1983, y = 81, rule = EV2QuadColor
25.3F.3F.3F133.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.
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61.3F.3F.3F$25.F3.F3.F.F61.3F.3F.3F61.F3.F3.F.F61.F3.F3.F.F61.F3.F3.F
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[[ THUMBNAIL THUMBSIZE 2 WIDTH 1200 HEIGHT 400 ]]
Please enable Javascript to view this LifeViewer.
Block replacements
Sometimes, a block that fails only needs to be supported with another catalyst, not replaced entirely. Take this, for example:
x=9, y = 9, rule = LifeHistory
2.2A$2.2A2$5.3D2$7.2A$.3A3.2A$.A.A$.A.A!
[[ GRID THUMBNAIL THUMBSIZE 2 ]]
Please enable Javascript to view this LifeViewer.
The catalyst almost works, but then an extra blinker, shown in red, destroys it. If only we could get rid of that blinker...
Oh, right! We can use what we just learned in this tutorial! Adding an extra fishhook suppresses the blinker and allows the catalyst to work:
x=12, y = 10, rule = B3/S23
11bo$2b2o5b3o$2b2o4bo$8b2o3$7b2o$b3o3b2o$bobo$bobo!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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This trick works in a variety of circumstances where a block fails because unwanted cells are born to one side. Also, the fishhook can often be replaced by a block. This sometimes works even if a fishhook doesn't work.
x=169, y = 44, rule = B3/S23
98bo$99bo16b2o11b4o$3bo43bo19bo13b2o15b2o18bo7b2o21bo$2b2o14b2o27bo18b
o14b3o10b3ob2o14b2o3bo7bo17b2obo14bo$2b2o12bob2o12bo16bobo13bo14bob2o
12bobo13bo14bo18b3o13b3o$3o13b3o13b3o14bobo13bobo12b3o13b3o14bobo12b3o
15b2o13bobo$bo15bo15bo16bo15bo14bo15bo16bo14bo15bo16bo2$b2o14b2o14b2o
14b2o14b2o14b2o14b2o14b2o14b2o14b2o14b2o$b2o14b2o14b2o14b2o14b2o14b2o
14b2o14b2o14b2o14b2o14b2o8$98bo$99bo16b2o11b4o$3bo43bo19bo13b2o15b2o18b
o7b2o21bo$2b2o14b2o27bo18bo14b3o10b3ob2o14b2o3bo7bo17b2obo14bo$2b2o12b
ob2o12bo16bobo13bo14bob2o12bobo13bo14bo18b3o13b3o$3o13b3o13b3o14bobo13b
obo12b3o13b3o14bobo12b3o15b2o13bobo$bo15bo15bo16bo15bo14bo15bo16bo14b
o15bo16bo2$b2o14b2o14b2o14b2o14b2o14b2o14b2o14b2o14b2o14b2o14b2o$b2o2b
2o10b2o2b2o10b2o2b2o10b2o2b2o10b2o2b2o10b2o2b2o10b2o2b2o10b2o2b2o10b2o
2b2o10b2o2b2o10b2o2b2o$5bobo13bobo13bobo13bobo13bobo13bobo13bobo13bob
o13bobo13bobo13bobo$7bo15bo15bo15bo15bo15bo15bo15bo15bo15bo15bo$7b2o14b
2o14b2o14b2o14b2o14b2o14b2o14b2o14b2o14b2o14b2o5$98bo$99bo16b2o11b4o$
3bo43bo19bo13b2o15b2o18bo7b2o21bo$2b2o14b2o27bo18bo14b3o10b3ob2o14b2o
3bo7bo17b2obo14bo$2b2o12bob2o12bo16bobo13bo14bob2o12bobo13bo14bo18b3o
13b3o$3o13b3o13b3o14bobo13bobo12b3o13b3o14bobo12b3o15b2o13bobo$bo15bo
15bo16bo15bo14bo15bo16bo14bo15bo16bo$5b2o14b2o14b2o14b2o14b2o14b2o14b
2o14b2o14b2o14b2o14b2o$b2o2b2o10b2o2b2o10b2o2b2o10b2o2b2o10b2o2b2o10b
2o2b2o10b2o2b2o10b2o2b2o10b2o2b2o10b2o2b2o10b2o2b2o$b2o14b2o14b2o14b2o
14b2o14b2o14b2o14b2o14b2o14b2o14b2o!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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Also, if the fishhook recovers too quickly but otherwise works, then like other examples where a fishhook recovers too quickly but otherwise works, it can sometimes be replaced with an eater 2.
x=33, y = 14, rule = B3/S23
o3bo14bo3bo$obo16bobo$2b2obo15b2obo$2b3o16b3o$4bo18bo2$3b2o17b2o$3b2o
2b2o13b2o2b2obo$7bobo16b2ob3o$9bo22bo$9b2o15b2ob3o$27bobo$27bobo$28bo!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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Another example where a block catalyst can be fixed by supporting the block with another catalyst comes from the following example, where the block is turned into a first cousin of the century then crashes into a boat.
x=5, y = 8, rule = B3/S23
b2o$b2o3$3o$obo$3bo$4bo!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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In this case, the block can be supported by another block. In fact, two positions work.
x=24, y = 8, rule = B3/S23
5b2o13b2o$2o3b2o13b2o$2o13b2o$15b2o$4b3o12b3o$4bobo12bobo$7bo14bo$8bo14bo!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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This trick only works if there is something for the century cousin to crash into (and even then, not always), but luckily, there is an actual replacement catalyst for when the block is turned into a century cousin with nothing to hit.
x=19, y = 10, rule = B3/S23
o11bo$b3o9b3o$2bo11bo2$2b2o10b2o2bo$2b2o9bob4o$11b3o$10bo3b3o$11b3o2bo$13bo!5b2o13b2o$2o3b2o13b2o$2o13b2o$15b2o$4b3o12b3o$4bobo12bobo$7bo14bo$8bo14bo!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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There is another replacement catalyst for when the block is turned into an L-tetromino (a common beehive predecessor).
x=22, y = 14, rule = B3/S23
3bo15bo$3bo15bo$3bo15bo$3bo15bo$3o13b3o$bo15bo2$b2o14b2o$b2o12bo2bo$15b
2obobo$18b2obo$15b3o3bo$15bo2b3o$18bo!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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It should be noted that when a block fails in one of the most recent two ways, it can often be replaced with a hook with tail (although the hook with tail is not a replacement catalyst for the block in the strictest sense).
x=17, y = 25, rule = B3/S23
15bo$15bo$15bo$o14bo$b3o8b3o$2bo10bo2$2b2o9b2o$2b2o9b2o6$15bo$15bo$15b
o$o14bo$b3o8b3o$2bo10bo2$bobo8bobo$b2obo7b2obo$4bo10bo$4b2o9b2o!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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If a block is turned into a P-pentomino in a certain way, it can be replaced with a boat—or a fishhook bridge fishhook.
x=32, y = 9, rule = B3/S23
bo10bo10bo$4obo5b4obo5b4obo$4bo10bo10bo2$4b2o9b2o9b2o$4b2o9bobo8bobo$
16bo7bobob3o$24b2o5bo$30b2o!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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There is another replacement catalyst for another way in which the block is sometimes turned into a P-pentomino.
x=20, y = 13, rule = B3/S23
obo11bobo$b2o12b2o$3bobo11bobo$3bobo11bobo$4bo13bo2$3b2o12b2o$3b2o12b
2o$14bo$14b5o$18bo$16bo$16b2o!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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In addition, there is a third way in which a block is sometimes turned into a P-pentomino. In this case, it can be replaced with a claw with tail supported by a fishhook.
x=21, y = 10, rule = B3/S23
3bo13bo$3bo13bo$obo11bobo$bo13bo2$b2o12b2o$b2o8b2o2bo2bo$10bobo3b2obo
$10bo8bo$9b2o8b2o!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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This also works if it's turned into an L-tetromino.
x=21, y = 10, rule = B3/S23
2bo13bo$3bo13bo$obo11bobo$bo13bo2$b2o12b2o$b2o8b2o2bo2bo$10bobo3b2obo
$10bo8bo$9b2o8b2o!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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For one particular type of block catalysis (specifically where the block is turned into a grin but not through the six-cell grin parent in Pentoad 2 ), the block can be replaced with a long hook with tail. For example, if a block is used with the eater 5 (which will be explained next) in this case, the chaos hits and destroys it (then destroys the tub with tail).
x=9, y = 10, rule = B3/S23
4bo$3bo3b2o$4bo2b2o$5b2o$2o$2o3bo$4bobo$5bobo$7bo$7b2o!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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Replacing the block with a long hook with tail avoids this.
x=10, y = 11, rule = B3/S23
5bo$4bo3b2o$5bo2b2o$6b2o2$b2o3bo$bo3bobo$2bo3bobo$3bo4bo$3o5b2o$o!
[[ GRID THUMBNAIL THEME 6 THUMBSIZE 2 ]]
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Here is a block replacement guide by Entity Valkyrie and MathAndCode:
x=1333, y = 81, rule = EV2QuadColor
26.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.
3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.
3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.3F61.3F.3F.
3F$26.F3.F3.F.F61.F3.F3.F.F61.F3.F3.F.F61.F3.F3.F.F61.F3.F3.F.F61.F3.
F3.F.F61.F3.F3.F.F61.F3.F3.F.F61.F3.F3.F.F61.F3.F3.F.F61.F3.F3.F.F61.
F3.F3.F.F61.F3.F3.F.F61.F3.F3.F.F61.F3.F3.F.F61.F3.F3.F.F61.F3.F3.F.F
61.F3.F3.F.F61.F3.F3.F.F$26.F3.2F2.F.F61.F3.2F2.F.F61.F3.2F2.F.F61.F3.
2F2.F.F61.F3.2F2.F.F61.F3.2F2.F.F61.F3.2F2.F.F61.F3.2F2.F.F61.F3.2F2.
F.F61.F3.2F2.F.F61.F3.2F2.F.F61.F3.2F2.F.F61.F3.2F2.F.F61.F3.2F2.F.F61.
F3.2F2.F.F61.F3.2F2.F.F61.F3.2F2.F.F61.F3.2F2.F.F61.F3.2F2.F.F$26.F.F
.F3.F.F61.F.F.F3.F.F61.F.F.F3.F.F61.F.F.F3.F.F61.F.F.F3.F.F61.F.F.F3.
F.F61.F.F.F3.F.F61.F.F.F3.F.F61.F.F.F3.F.F61.F.F.F3.F.F61.F.F.F3.F.F61.
F.F.F3.F.F61.F.F.F3.F.F61.F.F.F3.F.F61.F.F.F3.F.F61.F.F.F3.F.F61.F.F.
F3.F.F61.F.F.F3.F.F61.F.F.F3.F.F$26.3F.3F.F.F61.3F.3F.F.F61.3F.3F.F.F
61.3F.3F.F.F61.3F.3F.F.F61.3F.3F.F.F61.3F.3F.F.F61.3F.3F.F.F61.3F.3F.
F.F61.3F.3F.F.F61.3F.3F.F.F61.3F.3F.F.F61.3F.3F.F.F61.3F.3F.F.F61.3F.
3F.F.F61.3F.3F.F.F61.3F.3F.F.F61.3F.3F.F.F61.3F.3F.F.F2$30.F.F69.F.F69.
F.F69.F.F69.3F69.3F69.F.F69.F.F69.3F69.3F69.3F69.F.F69.3F69.3F69.3F69.
3F69.3F69.3F69.3F$30.F.F69.F.F69.F.F69.F.F71.F71.F69.F.F69.F.F71.F69.
F.F69.F71.F.F71.F69.F71.F71.F71.F71.F71.F$30.3F69.3F69.3F69.3F71.F69.
3F69.3F69.3F69.3F69.3F69.3F69.3F69.3F69.3F69.3F69.3F69.3F69.3F69.3F$32.
F71.F71.F71.F71.F69.F73.F71.F71.F69.F.F69.F.F71.F69.F71.F.F69.F.F71.F
71.F71.F71.F$32.F71.F71.F71.F71.F69.3F71.F71.F69.3F35.2D32.3F69.3F71.
F69.3F69.3F69.3F69.3F69.3F69.3F69.3F$142.D503.D$143.3D497.D.D217.2D$644.
D220.D$19.H71.H71.H71.H71.H71.H71.H71.H71.H71.H71.H71.H51.D19.H71.H71.
H71.H71.H71.H51.D.D17.H$19.2H47.D22.2H70.2H70.2H70.2H70.2H70.2H70.2H70.
2H70.2H70.2H70.2H49.2D19.2H70.2H50.D19.2H7.A40.D.D19.2H70.2H70.2H51.D
18.2H6.2A$2D13.7H46.D3.2D13.7H50.2D13.7H65.7H49.2D14.7H8.2A55.7H7.3A41.
D13.7H49.2D14.7H65.7H9.A38.3D14.7H9.A40.2D13.7H9.A40.2D13.7H6.3A38.D2.
D14.7H9.A55.7H8.2A37.D3.D13.7H4.2A3.A39.D15.7H65.7H46.D18.7H49.D15.7H
7.A$.2D.2E9.8H8.2E37.D2.2D.2E9.8H8.2E36.2D2.2D.2E9.8H8.2E39.2D2.2E9.8H
6.A.2E39.2D2.2E9.8H9.E40.D2.2E9.8H8.FE40.2D.2E9.8H7.A2E40.D2.2E9.8H7.
A2E40.D2.2E9.8H8.FE37.D2.D2.2E9.8H8.FE41.D.2E9.8H8.FE37.2D.2D.2E9.8H8.
2E38.D.D2.2E9.8H3.A4.FE39.D3.2E9.8H8.FE36.D3.2D.2E9.8H8.FE40.D2.2E9.8H
8.2E38.D.D2.2E9.8H8.2E35.2D.D.D2.2E9.8H8.2E38.D4.2E9.8H8.2E$.D2.2E9.7H
9.FE37.D2.D2.2E9.7H9.FE38.3D2.2E9.7H6.A2.FE38.D2.D.2E9.7H5.A3.FE41.D.
2E9.7H9.FE40.2D.2E9.7H9.FE40.D2.2E9.7H9.FE41.D.2E9.7H9.FE41.D.2E9.7H9.
FE41.D.2E9.7H8.AFE39.2D2.2E9.7H9.FE40.D2.2E9.7H9.FE41.D.2E9.7H5.A3.FE
37.2D.2D.2E9.7H9.FE38.2D3.2E9.7H5.2A2.FE38.D2.D.2E9.7H7.A.FE38.D2.D.2E
9.7H9.FE38.D2.D.2E9.7H9.FE40.2D.2E9.7H9.2E$19.2H7.A62.2H50.D19.2H7.A41.
D2.D17.2H7.A2.A40.2D17.2H7.A2.A41.D17.2H10.A37.D.2D18.2H52.D17.2H50.D
.D17.2H10.A38.D2.D17.2H10.A38.2D19.2H11.A39.D18.2H52.D17.2H6.A.3A40.D
18.2H8.A2.A58.2H10.A39.D.D17.2H11.A34.D.D.D.D17.2H11.A38.D.D17.2H11.A
39.2D17.2H$19.H9.3A59.H9.3A39.D19.H9.3A59.H9.2A60.H9.2A41.D18.H50.D20.
H71.H10.2A41.D17.H10.A39.2D.D17.H49.D.D19.H51.2D18.H51.D19.H71.H10.2A
59.H71.H9.A.A35.D23.H11.A59.H11.A59.H$317.2A40.D217.D286.D245.A$577.D
$576.D5$644.2D$142.D503.D368.2E25.2E$143.3D497.D.D217.2D149.E.E24.E.E
$644.D220.D148.E26.E$19.J71.H71.H71.J71.J56.2E13.J11.2E58.J71.H71.J71.
J71.J71.J51.D19.J71.J57.2E.E10.J12.2E.E55.J71.H71.H51.D.D17.J$19.2J47.
D22.2H70.2H70.2J70.2J56.E13.2J11.E44.2E.2E9.2J11.2E.2E40.2E.2E9.2H11.
2E.2E54.2J70.2J70.2J70.2J49.2D6.2E11.2J12.2E56.2J50.D4.E3.3E8.2J10.F3.
3E31.D.D19.2J70.2H70.2H51.D18.2J6.2A$2D13.7J46.D3.2D13.7H50.2D13.7H65.
7J49.2D14.7J8.2A45.E.2E6.7J7.2A.E.2E37.D4.E.E6.7J10.AE.E35.2D5.E.E6.7H
10.AE.E41.E9.7J9.AE37.3D14.7J50.2D13.7J9.A40.2D13.7J47.D2.D3.E2.E7.7J
8.AE2.E52.7J8.2A37.D3.D2.2E.E3.E3.7J9.FE.E3.E32.D15.7J65.7H46.D18.7H49.
D15.7J7.A$.2D.2E9.8J8.2E37.D2.2D.2E9.8H8.2E36.2D2.2D.2E9.8H8.2E39.2D2.
2E9.8J8.2E39.2D2.2E9.8J8.FE40.D2.2E.E7.8J8.FE.E38.2D.E3.E6.8J7.AE3.E37.
D2.E3.E6.8H7.AE3.E37.D2.E.E8.8J8.F.E36.D2.D2.2E9.8J8.2E41.D.2E.2E6.8J
8.FE.2E34.2D.2D.2E9.8J8.FE38.D.D2.3E8.8J8.F2E38.D3.2E.2E6.8J8.FE.2E33.
D3.2D5.E.E4.8J12.E.E35.D2.2E9.8J8.2E38.D.D2.2E9.8H8.2E35.2D.D.D2.2E9.
8H8.2E38.D15.8J$.D2.2E9.7J9.FE37.D2.D2.2E9.7H9.FE38.3D2.2E9.7H6.A2.FE
38.D2.D.2E9.7J9.FE41.D.2E9.7J9.FE40.2D.E2.E7.7J9.F2.E38.D2.4E.2E4.7J9.
F3E.2E36.D.4E.2E4.7H9.F3E.2E36.D.2E9.7J9.FE41.D.E.E8.7J9.E.E38.2D2.2E
.E2.E4.7J9.FE.E2.E35.D2.E.E.2E5.7J9.E.E.2E37.D12.7J48.2D.2D.2E.E2.E4.
7J9.FE.E2.E33.2D3.5E.2E3.7J9.F4E.2E32.D2.D.2E2.2E5.7J9.FE2.2E34.D2.D.
2E2.2E5.7H9.FE2.2E34.D2.D.2E2.2E5.7H9.FE2.2E36.2D.2E9.7J9.2E$19.2J10.
A59.2H7.A2.A39.D19.2H7.A41.D2.D17.2J51.2D17.2J9.2A41.D3.2E.2E9.2J10.A
2E.2E32.D.2D6.E.E9.2J13.E.E36.D5.E.E9.2H13.E.E34.D.D17.2J10.A38.D2.D3.
E13.2J11.E37.2D7.E.2E8.2J11.A.E.2E34.D5.E.E10.2J9.2A.E.E37.D2.3E12.2J
10.F2E38.D6.E.2E8.2J11.A.E.2E38.E4.E9.2J9.AF4.E34.D.D6.2E9.2J11.A2.2E
30.D.D.D.D6.2E9.2H11.A2.2E34.D.D6.2E9.2H11.A2.2E35.2D3.E13.2J11.E$19.
J9.A61.H9.A41.D19.H9.A3.A57.J13.A57.J52.D5.E.E10.J13.E.E34.D7.E2.E9.J
11.A.E2.E41.E2.E9.H10.2A.E2.E36.D17.J10.A39.2D.D17.J49.D.D7.E11.J14.E
36.2D4.2E2.E9.J11.AFE2.E34.D4.E2.E11.J10.AE2.E44.E11.J14.E42.3E.E9.J12.
3E.E54.J47.D23.H71.H56.E14.J11.E$3.2E24.AFE43.2E24.AFE45.2E25.FE43.2E
25.FE109.D6.E.E24.E.E43.2E25.2E43.2E25.2E37.D148.2E25.2E44.2E22.A2.2E
36.D5.2E25.2E43.2E25.2E44.E.2E23.E.2E134.A118.E26.E$3.2E25.2E43.2E25.
2E45.E26.E44.E26.E42.2E25.2E47.E26.E182.D219.2E25.2E113.E.E2.2E20.E.E
2.2E42.E26.E40.E26.FA43.E26.EA44.E24.A.E44.3E24.3E$150.3E24.3E42.3E24.
3E39.2E25.2E256.D221.E26.E113.2E2.E2.E19.2E2.E2.E40.2E25.2E39.E.E24.E
.E42.E.E24.E.E43.E.E24.E.E45.E26.E$152.E26.E44.E26.E546.E.E24.E.E116.
2E25.2E109.2E25.2E43.2E25.2E45.E26.E$799.2E25.2E4$142.D225.2E$143.3D221.
E.E25.2E466.2D$363.2E2.E26.E.E43.E26.E44.E26.E43.2E25.2E253.D$19.J71.
J71.J71.J71.J55.E.E.2E21.2E2.E43.3E10.J13.3E42.3E10.J13.3E42.E.E10.J13.
E.E251.D6.2E11.J13.2E272.J71.J$19.2J47.D22.2J70.2J70.2J70.2J56.E.E22.
E.E.2E41.E13.2J11.E44.E13.2J11.E45.E12.2J12.E252.2D6.E12.2J12.E273.2J
70.2J$2D13.7J46.D3.2D13.7J50.2D13.7J65.7J49.2D14.7J8.2A44.E2.E11.J12.
E.E38.D4.E8.7J10.AE37.2D5.E8.7J10.AE43.2E8.7J9.A2E251.D2.D3.E.E8.7J8.
AE.E269.7J46.D18.7J$.2D.2E9.8J8.2E37.D2.2D.2E9.8J8.2E36.2D2.2D.2E9.8J
8.2E39.2D2.2E9.8J8.2E39.2D2.2E9.8J8.FE40.D2.3E12.2J10.F2.E38.2D.E.E8.
8J7.AE.E39.D2.E.E8.8J7.AE.E39.D2.E10.8J8.F255.D.D2.2E9.8J8.FE254.D.D2.
2E9.8J8.2E35.2D.D.D2.2E9.8J8.2E$.D2.2E9.7J9.FE37.D2.D2.2E9.7J9.FE38.3D
2.2E9.7J9.FE38.D2.D.2E2.2E5.7J9.FE2.2E37.D.2E9.7J9.FE40.2D12.7J9.F2E39.
D2.2E9.7J9.FE41.D.2E9.7J9.FE41.D.3E8.7J9.F2E256.D12.7J265.D2.D.2E2.2E
5.7J9.FE2.2E34.D2.D.2E2.2E5.7J9.FE2.2E$19.2J70.2J50.D19.2J10.A38.D2.D
6.2E9.2J11.A2.2E35.2D17.2J10.A41.D2.3E8.8J46.D.2D18.2J52.D17.2J50.D.D
5.E11.2J10.A2.E254.D2.2E13.2J10.FE250.D.D.D.D6.2E9.2J11.A2.2E34.D.D6.
2E9.2J11.A2.2E$19.J13.A57.J13.A37.D19.J9.A61.J71.J52.D3.E2.E7.7J9.F2E
36.D20.J13.A57.J13.A39.D4.2E11.J10.A2.2E252.D4.E.E12.J10.AE.E249.D23.
J71.J$5.2E25.FE43.2E25.FE41.2E24.AFE43.E25.AF112.D5.E.E11.2J10.F2.E42.
2E25.FE43.2E25.FE39.D286.D5.E26.E357.A$5.E26.E44.E26.E42.2E25.2E42.E.
E24.E.E42.2E25.2E44.E.E.2E10.J12.E.E42.E26.E44.E26.E40.D292.2E25.2E257.
E26.E41.2E25.EFA$6.3E24.3E42.3E24.3E111.2E25.2E42.2E25.2E44.2E2.E22.E
.E.2E42.3E24.3E42.3E24.3E36.D578.E.E24.E.E40.2E25.2E$8.E26.E44.E26.E259.
E.E20.2E2.E45.E26.E44.E26.E616.E26.E$368.2E24.E.E$395.2E6$235.J71.J935.
J$235.2J70.2J934.2J$231.7J49.2D14.7J8.2A900.D18.7J$216.2D2.2E9.8J6.A.
2E39.2D2.2E9.8J8.FE899.2D.D.D2.2E9.8J8.2E$215.D2.D.2E9.7J5.A3.FE41.D.
2E9.7J9.FE902.D2.D.2E2.2E5.7J9.FE2.2E$214.D2.D17.2J7.A2.A40.2D17.2J10.
A903.D.D6.2E9.2J11.A2.2E$235.J9.2A60.J935.J$223.2E25.2E64.A$219.E3.2E
21.E3.2E37.2E25.2FA909.E26.E$218.E.E24.E.E40.E.E24.E.E910.3E24.3E$217.
E.E24.E.E39.3E.E.E20.3E.E.E911.E26.E$217.E26.E40.E5.2E19.E5.2E910.2E25.
2E$216.2E25.2E40.2E25.2E!
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Boat replacements Here is an example of a boat in need:
x=3, y = 8, rule = LifeHistory
.A$2.A$3A2$D$.A$A.A$.2A!
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In this example, the white cell at generation 4 gets turned on when it shouldn't. We have a fix for this, as usual. Replace the boat with a tub with tail and block (this catalyst is called an eater 5 or tub-with-tail eater :
x=9, y = 10, rule = B3/S23
5bo$6bo$4b3o2$2o$2o3bo$4bobo$5bobo$7bo$7b2o!
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Boats can also fail much more spectacularly:
x=8, y = 4, rule = B3/S23
6bo$3o2bobo$obo3b2o$obo!
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In this case, the boat can be replaced by this (often called the "gourmet catalyst" due to its use in gourmet ):
x=10, y = 10, rule = B3/S23
8b2o$7bobo$7bo$6b2o2$6b2o$3o2bobo$obo3bo$obo4b3o$9bo!
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Note that this doesn't always work, since it requires a spark to recover properly.
These replacement catalysts also work for failed tertiary boat catlayses. Here are two examples:
x=35, y = 29, rule = B3/S23
7b2o18b2o$6bobo17bobo$7bo19bo$30bo$8b4o16b2obo$9b2o17b2obo$11bo16bo4b
o$10bo17bo4bo$9bo24bo10$8b2o10b2o6b2o$8bo11bo7bo$6bobo12b3ob2obo$5bob
o15bobobo$2o4bo19bo$2o27bo$7b4o16b2obo$8b2o17b2obo$10bo16bo4bo$9bo17b
o4bo$8bo24bo!
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For the secondary boat catalysis, there will sometimes be a blinker next to the boat when it recovers that then destroys the boat.
x=31, y = 6, rule = B3/S23
3bo11bo10bo$3bo11bobo9bo2bo$3bo2bo8bo11bobo$bo3b2o6bo11bo4bo$obo3bo5b
obo9bobo3bo$2o10b2o10b2o4bo!
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When this happens, the boat can be replaced with a beehive with tail.
x=34, y = 8, rule = B3/S23
6bo11bo10bo$6bo11bobo9bo2bo$6bo2bo8bo11bobo$3b2o3b2o5b2o10b2o4bo$2bo2b
o3bo4bo2bo8bo2bo3bo$bob2o8bob2o8bob2o4bo$bo11bo11bo$2o10b2o10b2o!
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This also works if the part of the blinker that is farther away from the boat is modified.
x=20, y = 10, rule = B3/S23
7bo11bo$5b2o10b2o$3bo11bo$3bo11bo$3bobo9bobo$bo10b2o$obo8bo2bo$2o8bob
2o$10bo$9b2o!
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Snake replacements Sometimes, the snake needs to be replaced them with a similar catalyst which does the same thing but might have better clearance. For example, if a snake is required to be in close proximity to a fishhook, the fishhook's interaction might destroy the snake (and subsequently the fishhook). In this case, replacing the snake with a higher-clearance second fishhook can prevent the interaction:
x=36, y = 9, rule = B3/S23
7bo26bo$2o4bo20b2o4bo$bo4b3o8bo10bo4b3o$o18bo5b3o$2o23bo$3b2o6bobobob
obobo8b2o$4bo26bo$b3o15bo8b3o$bo15bo10bo!
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A problem that sometimes occurs with snake catalyses is that a certain cell above the snake (marked in red) will be born when the snake is supposed to be done interacting. When this happens, try replacing the snake with a hook with tail.
x=18, y = 19, rule = LifeHistory
2A.2A8.3A$2.C.D9.C.D2$3.2A10.2A$4.A11.A$3.A11.A$3.2A10.2A6$2A.2A8.3A$
2.C.D9.C.D2$.A.A9.A.A$.2A.A8.2A.A$4.A11.A$4.2A10.2A!
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Tub replacements Sometimes, a single dot at the end of the tub parent is replaced with a line of three cells, causing the tub to turn into a block instead of recovering:
x=24, y = 12, rule = LifeHistory
22.2A$21.2A$20.2A$A5.A2$.2A.2A$3.A$6.D15.D$6.D15.D$4.A15.A$3.A.A13.A.
A$4.A15.A!
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When this occurs, the tub should be replaced with this catalyst:
x=30, y = 18, rule = B3/S23
23b2o$22b2o$21b2o$bo5bo2$2b2ob2o$4bo3$5bo15bo$4bobo13bobo$3bobo13bobo$
b3o2b3o3b2o3b3o2b3o3b2o$o3b2o3bo2b2o2bo3b2o3bo2b2o$b3o2b2obo7b3o2b2obo
$3bobo2bo10bobo2bo$4bobo13bobo$5bo15bo!
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If this line of three cells is connected to something at the other end, a boat supported by a fishhook works:
x=21, y = 20, rule = LifeHistory
3.A$3.A10.A$3AD9.2D$3A.D8.2AC$4.D10.D$2.A10.A$.A.A8.A.A$2.A10.A3$3.A$
3.A10.A$3AD9.2D$3A.D8.2AC$4.D10.D$2.A10.A$.A.A2.2A4.A.A2.2A$.2A3.A.A3.
2A3.A.A$8.A10.A$8.2A9.2A!
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If the line is instead four or more cells long, a certain 15-cell catalyst works:
x=18, y = 23, rule = LifeHistory
16.A$6.A9.AD$2.A3.A9.AD$3.A.A.D9.D$4.A2.D7.2AC$7.D9.D$5.A9.A$4.A.A7.A
.A$5.A9.A3$16.A$6.A9.AD$2.A3.A9.AD$3.A.A.D9.D$4.A2.D7.2AC$7.D9.D$5.A9.
A$4.A.A7.A.A$3.A.A7.A.A$.3A.A.A3.3A.A.A$A5.2A2.A5.2A$2A8.2A!
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Ship replacements The ship family is fairly unique as a catalyst family. For most catalyst families, one places the namesake catalyst expecting it to work, and the replacement catalysts are reserves. However, a ship will almost always fail when attempting a ship-type catalysis, and it is much more often the case that one of the replacement catalysts works. However, I think that it is worth initially placing lone ships (as opposed to initially placing a replacement catalyst) for three reasons:
It takes less time to draw a ship than to draw any of the replacement catalysts.
It is easier to see which replacement catalyst, if any, will work by observing a lone ship than by observing any single replacement catalyst.
A lone ship will occasionally work, and I don't want to miss when that happens. (If a lone ship works, none of the replacement catalysts will work.) Often, the ship is turned into a loaf. Adding a fishhook turns it back into a ship:
x=72, y = 30, rule = LifeHistory
14.A$16.2A$16.4A9.A.A22.A11.A$.A11.A4.A7.A4.A7.A15.A10.A$2.A.A9.3A10.
3A10.2A11.A.A12.A$3.A12.A12.A12.A12.A12.A$64.A.A$4.2A11.2A11.2A11.2A11.
2A8.A2.2A$4.A.A10.A.A10.A.A10.A.A10.A.A10.A.A$4.D2A10.D2A10.D2A10.D2A
10.D2A10.D2A6$14.A$16.2A$16.4A9.A.A22.A11.A$.A11.A4.A7.A4.A7.A15.A10.
A$2.A.A9.3A10.3A10.2A11.A.A12.A$3.A12.A12.A12.A12.A12.A$64.A.A$4.2A11.
2A11.2A11.2A11.2A8.A2.2A$4.A.A10.A.A10.A.A10.A.A10.A.A10.A.A$5.2A11.2A
11.2A11.2A11.2A11.2A2$2.2A11.2A11.2A11.2A11.2A11.2A$3.A12.A12.A12.A12.
A12.A$3A10.3A10.3A10.3A10.3A10.3A$A12.A12.A12.A12.A12.A!
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If the loaf parent has an extra cell in a certain position (so that it becomes a great-uncle of the I-heptomino), there's another replacement catalyst that works (which was discovered fairly recently to use in the R49 conduit, so it is often called the "R49 catalyst"):
x=14, y = 29, rule = LifeHistory
3.A$4.2A2$4.A.A$5.A2$5.D2A$6.A.A$6.D2A7$3.A$4.2A2$4.A.A$5.A2$6.2A$3.A
.A2.A$.3A.A.2A$A4.A$.3A.A4.2A$3.2A5.A$11.3A$13.A!
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It can work even if the chaos doesn't leave the ship/I-relative.
x=74, y = 28, rule = LifeHistory
4.A59.A$4.A2.A18.A39.2A$4.A.A17.A.A17.A.A16.2A$5.A19.A19.A19.A2$5.D2A
17.D2A17.D2A17.D2A$6.A.A17.A.A17.A.A17.A.A$6.D2A17.D2A17.D2A17.D2A8$4.
A59.A$4.A2.A18.A39.2A$4.A.A17.A.A17.A.A16.2A$5.A19.A19.A19.A2$6.2A18.
2A18.2A18.2A$3.A.A2.A14.A.A2.A14.A.A2.A14.A.A2.A$.3A.A.2A12.3A.A.2A12.
3A.A.2A12.3A.A.2A$A4.A14.A4.A14.A4.A14.A4.A$.3A.A4.2A9.3A.A4.2A9.3A.A
4.2A9.3A.A4.2A$3.2A5.A12.2A5.A12.2A5.A12.2A5.A$11.3A17.3A17.3A17.3A$13.
A19.A19.A19.A!
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When considering replacing the ship with an R49 catalyst, it is very important that the marked cell has three live neighbors on generation two.
x=5, y = 7, rule = LifeHistory
2.A$A.A$.A$3.D$2.2A$2.A.A$3.2A!
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If the marked cell only has two live neighbors on generation two, don't bother placing an R49 catalyst; it won't work.
x=54, y = 27, rule = LifeHistory
4.A42.A$4.A.A16.2A19.A.A$5.A19.A19.A$7.D19.D19.D$6.2A18.2A18.2A$6.A.A
17.A.A17.A.A$7.2A18.2A18.2A9$4.A42.A$4.A.A16.2A19.A.A$5.A19.A19.A2$6.
2A18.2A18.2A$3.A.A2.A14.A.A2.A14.A.A2.A$.3A.A.2A12.3A.A.2A12.3A.A.2A$
A4.A14.A4.A14.A4.A$.3A.A4.2A9.3A.A4.2A9.3A.A4.2A$3.2A5.A12.2A5.A12.2A
5.A$11.3A17.3A17.3A$13.A19.A19.A!
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A fishhook bridge fishhook works when the ship turns into a certain blockade predecessor.
x=48, y = 31, rule = LifeHistory
.A38.A$.A20.A17.A2.A$2.A19.A16.A.A2.A$.A17.2A.A18.A2.A$.A19.A19.A2$.D
AC17.DAC17.DAC$.DC.C16.DC.C16.DC.C$2.D2C17.D2C17.D2C12$.A38.A$.A20.A17.
A2.A$2.A19.A16.A.A2.A$.A17.2A.A18.A2.A$.A19.A19.A2$2.2A18.2A18.2A$2.A
.A17.A.A17.A.A$A.A.3A13.A.A.3A13.A.A.3A$2A5.A12.2A5.A12.2A5.A$6.2A18.
2A18.2A!
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Lone ships, ship-fishhook pairs, and R49 catalysts are more likely to work when the cell that "activates" them survives into the next generation, while a fishhook bridge fishhook catalyst is more likely to work if by the next generation, the cell that "activated" it has died, and it has a two-cell edge to "slam" into. Common examples of the latter are a grin (like in 30P6.1 ) and a certain edgeshootable beehive predecessor.
x=18, y = 11, rule = LifeHistory
11.A$.A9.A$2.A9.A$2.A8.A$.C9.C2$2.2A8.2A$2.A.A7.A.A$A.A.3A3.A.A.3A$2A
5.A2.2A5.A$6.2A8.2A!
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While this is a trend, this is not a hard-and-fast rule. Here are demonstrations of this (mostly from earlier in this section):
x=65, y = 13, rule = LifeHistory
8.A19.A14.A15.A$A5.2A6.A14.A15.2A12.A$.A.2A10.2A10.A.A12.2A12.2A.A$.A
3.C11.C11.C14.C13.C2$6.2A10.2A10.2A13.2A12.2A$6.A.A9.A.A9.A.A9.A.A2.A
11.A.A$7.2A10.2A10.2A7.3A.A.2A9.A.A.3A$39.A4.A12.2A5.A$16.2A10.2A10.3A
.A4.2A12.2A$17.A11.A12.2A5.A$14.3A9.3A21.3A$14.A11.A25.A!
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For this reason, as well as the fact that a ship takes less time to draw than a fishhook bridge fishhook (and I can still tell whether or not a fishhook bridge fishhook will work by observing a ship), I place a long ship instead of a fishhook bridge fishhook even in situations that look like a fishhook bridge fishhook is the most likely ship-type catalyst to work.
Occassionally, instead of simply becoming the aforementioned blockade predecessor, the ship will become that blockade predecessor with three additional cells, and if one uses a fishhook bridge fishhook, it will mostly recover, but there will be three extra cells in the same position. When this happens (One only needs to observe this for one of those two catalysts.), a beehive works.
x=69, y = 43, rule = LifeHistory
62.A$2A2.A13.A44.2A$.A2.A14.2A18.A.A.A15.A$2.A2.A15.2A15.2A.2A17.2A.A
$2.A2D17.A2D13.A3.A2D17.A2D$4.D19.D19.D19.D$2.DAC17.DAC17.DAC17.DAC$
2.DC.C16.DC.C16.DC.C16.DC.C$3.D2C17.D2C17.D2C17.D2C9$62.A$2A2.A13.A
44.2A$.A2.A14.2A18.A.A.A15.A$2.A2.A15.2A15.2A.2A17.2A.A$2.A2D17.A2D
13.A3.A2D17.A2D$4.D19.D19.D19.D$3.2A18.2A18.2A18.2A$3.A.A17.A.A17.A.A
17.A.A$.A.A.3A13.A.A.3A13.A.A.3A13.A.A.3A$.2A5.A12.2A5.A12.2A5.A12.2A
5.A$7.2A18.2A18.2A18.2A7$62.A$2A2.A13.A44.2A$.A2.A14.2A18.A.A.A15.A$
2.A2.A15.2A15.2A.2A17.2A.A$2.A19.A15.A3.A19.A2$3.2A18.2A18.2A18.2A$2.
A2.A16.A2.A16.A2.A16.A2.A$3.2A18.2A18.2A18.2A!
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Bonus catalyses Here are some extra catalyses which might come in useful. This section is optional as the catalysts used are fairly rare.
Eater 3 You might notice that when you hit a loaf with a glider in a certain way, the loaf flips around:
x=15, y = 14, rule = B3/S23
2bo$obo$b2o$5b2o$4bo2bo$4bobo$5bo5$12b3o$12bo$13bo!
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This is quite inconvenient for us because we can't use the loaf again (unless we flip it back around with another glider as shown in the viewer, which is unlikely), but a stable catalyst does exist to turn the loaf back around. Here is the eater 3:
x=16, y = 15, rule = b3s23
2bo$obo$b2o$5b2o$4bo2bo2b2o$4bobo4bo2bo$5bo5bobobo$8b2obo2bo$8bo2bo$5b
o4bo$5b5o2$7bo$6bobo$7bo!
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There is also a drifty variant of the eater 3 that catalyzes in the same way, but recovers differently:
x=11, y = 10, rule = b3s23
o$b2o$2o7b2o$4b2obo2bo$3bobob3o$3bobo$b3ob5o$o3bo4bo$2o2bobo$5b2o!
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The eater 3 has some other applications besides eating gliders, for example the rectifier . I typically use the eater three when a fishhook fails on a corner (in at least one orientation), and there aren't any replacement catalysts that work.
x=37, y = 18, rule = B3/S23
3bo19bo$bo19bo$bo19bo$bo19bo$3b2o18b2o$4o16b4o$bo4b2o13bo4b2o$6bobo16b
o2bo2b2o$8bo16bobo4bo2bo$8b2o16bo5bobobo$29b2obo2bo$29bo2bo$26bo4bo$26b
5o2$28bo$27bobo$28bo!
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Also, there is an alternative way to restore the loaf's orientation that is sometimes useful for welding purposes.
x=22, y = 19, rule = B3/S23
20b2o$20b2o4$15b2obo$15b2ob3o$3o7b2o9bo$bo7bo2bo2b2ob3o$b3o5bobo4bobo
$10bo5bo$13b2obo$11bo2bob2o$7b2o2b3o$7bo$8b6o$13bo$10bobo$10b2o!
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Ship (again) The ship has a pseudo-transparent catalysis not similar to other catalysts where it deletes half of a traffic light :
x=7, y = 6, rule = B3/S23
b2o$obo$2o2$5bo$4b3o!
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This may seem pretty niche, but it is actually a fairly common application.
Loaf Besides its usage in the eater 3, the loaf has a pseudo-transparent catalysis that can eat a certain beehive predecessor or two block predecessors that are similar to each other.
x=32, y = 7, rule = B3/S23
o2$b3o8bob2o10b2o$5bo7bo3bo6b2o3bo$4bobo9bobo9bobo$4bo2bo8bo2bo8bo2bo
$5b2o10b2o10b2o!
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This type of loaf catalysis is used in Kazyan's method of restoring a block that has been turned into a beehive while generating a Herschel.
x=15, y = 18, rule = B3/S23
obo$b2o$bo8$8b2o$7bo2bo$8b2o2$12bo$11bobo$11bo2bo$12b2o!
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Hook with tail The hook with tail can serve as a rock:
x=54, y = 13, rule = B3/S23
43b2o2$26bo18bo$26bo16bo2bo4b2o$27bo2bo12bo2bo4bobo$27b3o14b3o5bo$b2o
b2o4b3o4b5o12bob3o$3bo7bo8bo14bo2$2bobo5bobo6bobo5bobo5bobo6bobo$bob2o
4bob2o5bob2o4bob2o4bob2o5bob2o$bo7bo8bo7bo7bo8bo$2o6b2o7b2o6b2o6b2o7b
2o!
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It does not care about orientation.
x=37, y = 13, rule = B3/S23
26b2o2$9bo18bo$9bo16bo2bo4b2o$10bo2bo12bo2bo4bobo$10b3o14b3o5bo$5o12b
ob3o$3bo14bo2$2bobo5bobo5bobo6bobo$2b2obo4b2obo4b2obo5b2obo$5bo7bo7bo
8bo$5b2o6b2o6b2o7b2o!
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Eater 4 The eater 4 primarily catalyses symmetrical objects. Its most common use is to catalyze a honey farm:
x=44, y = 15, rule = B3/S23
b2o$o2bo5b2o20b2o6b2o$3o7bo19bo2bo6bo$10bob2o16b3o7bob2o$9b2o2bo11bo13b
2o2bo$6bo4b2o12bo10bo4b2o$6b5o14bo10b5o$4b2o4bo23b2o4bo$5bo2b2o25bo2b
2o$5bobo27bobo$o2bobobo22bo2bobobo$4ob2o23b4ob2o$4bo29bo$2bobo27bobo$
2b2o28b2o!
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This can also come in handy sometimes; for example the recently-discovered L122 conduit.
In order for the eater 4 to recover, it needs to stay diagonally symmetric. If there is a line of two on each side, it will receive dot sparks on both sides, stay symmetric, and recover properly.
x=74, y = 14, rule = B3/S23
3bo5b2o21bo6b2o28b2o$3bo6bo20bo8bo22bo6bo$2bobo5bob2o16bo2b2o5bob2o17b
o2bo5bob2o$2o2bo4b2o2bo18bobo4b2o2bo17bo2bo4b2o2bo$2b2o2bo4b2o19b2o2b
o4b2o20bo2bo4b2o$6b5o25b5o21bo3b5o$4b2o4bo23b2o4bo23b2o4bo$5bo2b2o25b
o2b2o25bo2b2o$5bobo27bobo27bobo$o2bobobo22bo2bobobo22bo2bobobo$4ob2o23b
4ob2o23b4ob2o$4bo29bo29bo$2bobo27bobo27bobo$2b2o28b2o28b2o!
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If there is a line of three or more on each side, it will receive a dot spark on neither side, stay symmetric, and recover properly.
x=134, y = 14, rule = B3/S23
9b2o20b3o5b2o23bo4b2o22b2o4b2o28b2o$4bo5bo19bo3bo5bo23bo5bo23bo5bo23b
o5bo$4bo5bob2o16bo3bo5bob2o20bo5bob2o20bo5bob2o20bo5bob2o$4bo4b2o2bo16b
o3bo4b2o2bo20bo4b2o2bo20bo4b2o2bo20bo4b2o2bo$b3o2bo4b2o18b3o2bo4b2o17b
4o2bo4b2o18b3o2bo4b2o19b2o2bo4b2o$6b5o25b5o25b5o25b5o20bo4b5o$4b2o4bo
23b2o4bo23b2o4bo23b2o4bo23b2o4bo$5bo2b2o25bo2b2o25bo2b2o25bo2b2o25bo2b
2o$5bobo27bobo27bobo27bobo27bobo$o2bobobo22bo2bobobo22bo2bobobo22bo2b
obobo22bo2bobobo$4ob2o23b4ob2o23b4ob2o23b4ob2o23b4ob2o$4bo29bo29bo29b
o29bo$2bobo27bobo27bobo27bobo27bobo$2b2o28b2o28b2o28b2o28b2o!
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However, if there is a line of two on one side and a line of three or more on the other side, it will receive a dot spark on one side but not the other, so it will lose its symmetry and fail.
x=74, y = 15, rule = B3/S23
63bo$9b2o28b2o23bo4b2o$4bo5bo22bo6bo23bo5bo$4bo5bob2o19b2o5bob2o17bo2b
o5bob2o$2o2bo4b2o2bo20bo4b2o2bo17bo2bo4b2o2bo$2b2o2bo4b2o18b3o2bo4b2o
19b2o2bo4b2o$6b5o25b5o25b5o$4b2o4bo23b2o4bo23b2o4bo$5bo2b2o25bo2b2o25b
o2b2o$5bobo27bobo27bobo$o2bobobo22bo2bobobo22bo2bobobo$4ob2o23b4ob2o23b
4ob2o$4bo29bo29bo$2bobo27bobo27bobo$2b2o28b2o28b2o!
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Even if the interaction lasts unusually long, as long as the eater 4 maintains its symmetry, it still has a chance of recovering.
x=14, y = 14, rule = B3/S23
9b2o$2bo7bo$b2o7bob2o$3bo5b2o2bo$6bo4b2o$6b5o$4b2o4bo$5bo2b2o$5bobo$o
2bobobo$4ob2o$4bo$2bobo$2b2o!
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Finding new catalysts Mike Playle's Bellman is a search program specifically designed to search for new catalysts, given a reaction to be perturbed. It discovered the Snark , as well as many other highly notable patterns. This part of the tutorial hasn't been written yet, so consult the discussion thread and original documentation .
Another catalyst finding program is CatForce , which is a brute force placement program of certain given catalysts in a given area, and can also find transparent catalysts if they're restored quickly enough. It has also discovered quite a few interesting things, like B60 .
External links