It has been proposed that this page be moved to Fishhook due to the following reason: A Discord proposal from last month suggested "fishhook" would be better suited for the still life itself, and "eater 1" for its reaction. This will need some intense discussion on the talk page, as this is by no means a trivial rename.
Eater 1 (or fishhook or simply eater) is a 7-cellstill life and the smallest asymmetric still life, observed independently by several Life enthusiasts in 1971. The name "fishhook", which is still occasionally used, was suggested by Clement A. Lessner III and William P. Webb.
This still life is comprised of the normally unstable pre-block with a normally unstable tail attached. This pattern can also be seen as a trans version of the bookend.
Pre-block is not the only catalytic site on a fishhook. Its tail can be used as a rock that eats an unnamed 7-cellpolyplet; another example of this type of catalysis can be found at generation 74 of Fx153. Its tail and head can also trigger a boat-bit reaction, and in this manner it can be considered a G0 glider pair eater.
Eater 1 is the thirteenth most common still life on Adam P. Goucher's Catagolue, being less common than mango but more common than long barge. Among all still lifes with 7 cells, it is the third most common, being less common than long boat but more common than long snake.
It is also the seventeenth most common object overall on Catagolue, and the rarest object in Catagolue for which a 2-glider synthesis exists.
There is a perpendicular 2-glider collision that produces an eater 1 and a domino spark, the latter of which is consumed in four more ticks.
Several ways to drop an eater 1 on the reaction envelope are known, for example a two-stage four-glider recipe involving an intermediate pond. These can be useful for constructing larger patterns with tight space and/or time restrictions.