Water Bubble
Halves damage from Fire moves, doubles damage of Water moves, and prevents burns.
Full effect
When this Pokémon is hit by a Fire move, the damage is halved. When this Pokémon uses a Water move, the power is doubled. This Pokémon cannot be burned, and if it becomes burned, the burn is immediately cured.
In game description
Lowers the power of Fire-type moves that hit the Pokémon and prevents it from being burned.
Pokemon with Water Bubble
Using Water Bubble in Cobblemon
Abilities are passive and always active, so Water Bubble 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.