Emergency Exit
This Pokémon automatically switches out when its HP drops below half.
Full effect
After this Pokémon is hit by a move, if that move caused this Pokémon's HP to drop below half, it switches out.
In game description
The Pokémon, sensing danger, switches out when its HP becomes half or less.
Pokemon with Emergency Exit
Using Emergency Exit in Cobblemon
Abilities are passive and always active, so Emergency Exit 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.