Commander
Goes inside the mouth of an ally Dondozo if one is on the field.
Full effect
When the Pokémon enters a battle, it goes inside the mouth of an ally Dondozo if one is on the field. The Pokémon then issues commands from there.
In game description
When the Pokémon enters a battle, it goes inside the mouth of an ally Dondozo if one is on the field. The Pokémon then issues commands from there.
Pokemon with Commander
Using Commander in Cobblemon
Abilities are passive and always active, so Commander 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.