Generation V
Moody
Raises one stat and lowers another.
Detailed Effect
After each turn, one of this Pokémon's stats at random rises two stages, and another falls one stage. If a stat is already at 6 or -6 stages, it will not be chosen to be increased or decreased, respectively.
Pokémon With Moody
8 canonical Pokémon forms can have this Ability.
Remoraid 
Octillery 
Smeargle 
Snorunt 
Glalie 
Bidoof 
Bibarel 
Scovillain 
