Supersweet Syrup
Once per battle, when a Pokémon with Supersweet Syrup enters the battle, it lowers the evasion stat of all adjacent opponents by one stage.
Full effect
A sickly sweet scent spreads across the field the first time the Pokémon enters a battle, lowering the evasiveness of opposing Pokémon.
In game description
Lowers the evasion of opposing Pokémon by 1 stage when first sent into battle
Pokemon with Supersweet Syrup
Using Supersweet Syrup in Cobblemon
Abilities are passive and always active, so Supersweet Syrup 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.