Solid Rock
Decreases damage taken from super-effective moves by 1/4.
Full effect
This Pokémon takes 0.75× as much damage from moves that are super effective against it. This ability functions identically to Filter.
In game description
Reduces the power of supereffective attacks that hit the Pokémon.
Pokemon with Solid Rock
Using Solid Rock in Cobblemon
Abilities are passive and always active, so Solid Rock 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.