Adaptability

Full effect

This Pokémon inflicts twice as much damage with moves whose types match its own, rather than the usual same-type attack bonus of 1.5×.

In game description

Powers up moves of the same type as the Pokémon.

Using Adaptability in Cobblemon

Abilities are passive and always active, so Adaptability costs you nothing to run. If it is marked hidden on a species above, expect it to be harder to obtain: servers differ in whether hidden abilities come from breeding, an Ability Patch, or events.

See the Pokedex for which abilities each species can have, and IVs, EVs and breeding for how to actually pass one down.