- For the software, see Catalyst (search program)
- Do not confuse with catacryst.
A catalyst is an object that participates in a reaction but emerges from it unharmed. The term is mostly applied to still lifes, some small examples of which can act as catalysts in some situations, such as the block, ship, and tub; it can also be used for oscillators, spaceships, and other patterns. All eaters are catalysts, as are the still lifes and oscillators which form a conduit are examples of catalysts.
A relatively rare form of catalysis occurs in a transparent debris effect, where the catalyst in question is completely destroyed and then rebuilt. The term is also sometimes used for a modification of an active reaction in a rake by passing spaceships.