Effort values (EVs)
Effort values are points a Pokémon earns from the species it defeats, raising specific stats
From Ruby and Sapphire a Pokémon holds at most 510 EVs in total and 255 in one stat; X and Y lowered the per-stat cap to 252. Every 4 EVs add one stat point at level 100. Generations I and II used stat experience instead, up to 65,535 per stat, adding the defeated Pokémon's base stats to all five.
Main-series games; introduced in Generation I, Red and Green.
3 later changes
- Ruby and Sapphire replaced stat experience with EVs capped at 510 total and 255 per stat.
- Black and White applied EV gains to stats immediately instead of at the next level-up.
- X and Y set the per-stat cap to 252 and added Super Training.