The Evasion stat, or evasiveness, determines the percent chance that an opponent's move will miss. The initial value at the start of any battle is 100%. If the stat is decreased below 100% with a move such as Sweet Scent, then the opposing Pokémon has a better chance of connecting its move. If the stat is increased above 100% with a move suchas Double Team, the opposing Pokémon will have a harder time connecting its moves.Itwas called "evade" in Generation I.
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