These aren't necessarily "new" abilities, just currently existing abilities that I thought needed a buff or tweak.
>Magician
When this Pokemon hits the opposing Pokemon with a move of 100 BP or higher, it destroys their held item. (Doesn't effect Mega Stones, Z-Crystals, or signature items like Farfetch'd Stick)
>Long Reach
Physical moves used don't make contact. Moves effected in this way are boosted by x1.5 and have 100% accuracy.
>Berserk
Boosts both Attack & Special Attack by +1 when the Pokemon is brought to red health.
>Corrosion
The Pokemon can Poison the target, even if it's Steel or Poison type. Poison type moves are SE against Steel types.
>Battery
Boosts Special attacks by x1.5 after being hit by Electric moves.
>Grass Pelt
Boosts both defenses by 50% when Grassy Terrain is in effect.
>Damp
Explosion, Self-Destruct, and Mind Blown are unusable while this Pokemon is active. Fire type moves have their power decreases by 50% while this Pokemon is active.
>Overcoat
Protects Pokemon from Weather, Powder, and Status Effects.
>Snow Cloak
Boosts this Pokemon's evasion by +2 permanently after being in Hail for as long as it's active.
>Slush Rush
Doubles this Pokemon's speed permanantely after being in Hail for as long as it's in battle.
>Magma Armor + Flame Body + Flash Fire = Magma Flare, combined into one ability.
This Pokemon cannot be Frozen and Physical attacks used against it have a 30% chance to inflict Burn. This Pokemon absorbs Fire attacks and has either it's Attack or Special Attack depending on which stat is higher raised by +1 for the next move.
>Vital Spirit & Sweet Veil
This Pokemon cannot be put to Sleep. Moves used against this Pokemon that inflict Sleep instead boost it's Speed by +1.
>Unnerve
The opposing Pokemon can no longer eat berries or use it's item.
>Liquid Voice
All attacks become Sound based attacks and bust through Substitute and Reflect like effects. Moves that bust through said things have their power raised by x1.5.