What are all the abilities that have negative effects?

Example: Defeatist.

Pleaselog inorregisterto add a comment.

There are also some abilities that have a negative effect as well as a positive one, but these are all the ones that are only negative. I only included the purely negative ones, because the other ones wouldn’t be negative abilities if they have an up-side.

Source -http://bulbapedia.bulbagarden.net/wiki/Ability

okay, let’s run through them

bad, no matter how you look at it

Truant, it limets only 1 move every 2 turnsDefeatist (as you said), halves attack and special attack when at half or below HPSlow Start, for the first 5 turns, attack and speed are halvedStall, your Pokemon always moves lastNormalize, turns all moves into normal types (so you will never land a super effective hit and never hit a ghost Pokemon)Klutz, can’t hold any item

not bad, yet not good

Run Away, makes escaping easierilluminate, increases wild battle encounter chanceHeavy metal, doubles weight, can be good, can be bad (especially if the opponent has grass knot)weak armour, boosts speed at the cost of defence, if you are sweeping, you need speed, but with low defence, your turns are limited.

Some of these Abilities, such as Normalize, can be considered to be positive under certain conditions.

Air LockCloud NineContraryDefeatistDry SkinHeavy MetalHustleKlutzLight MetalMoodyNo GuardNormalizeRivalryRun AwaySheer ForceSimpleSlow StartSolar PowerStallTruantUnawareWeak Armor

Source:Bulbapedia