So I just had a single battle against a guy with a chansey. I had psychic terrain active and he managed to get a triple minimize, gaining a ridiculously high evasiveness stat. After that, though, I used Psychic and hit 4 times in a row until it fainted. Was I just really lucky or did my terrain somehow affect the move?
You were just really lucky. None of the terrain moves effect accuracy. Each Terrain gives the following effects:
Electric Terrain • grounded Pokémon cannot fall asleep • power of Electric moves increases by 50% • causes Pokémon with the ability Surge Surfer to double their Speed • activates the held item Electric Seed, raising the holder's Defence by one stage • turns Nature Power into Thunderbolt Grassy Terrain • grounded Pokémon receive 1/16 of their health back each turn • power of Earthquake, Bulldoze and Magnitude is halved • power of Grass-type moves increases by 50% • activates the held item Grassy seed, raising the holder's Defence by one stage • turns Nature Power into Energy Ball Misty Terrain • protects grounded Pokémon from status conditions • power of Dragon-type moves is halved • activates the item Misty Seed, raising the holder's Sp. Defence by one stage • turns Nature Power into Moonblast Psychic Terrain • prevents priority moves from being used (Shadow Sneak, Aqua Jet, etc.) • power of Psychic moves increases by 50% • activates the held item Psychic Seed, raising the holder's Sp. Defence by one stage • turns Nature Power into Psychic
Electric Terrain • grounded Pokémon cannot fall asleep • power of Electric moves increases by 50% • causes Pokémon with the ability Surge Surfer to double their Speed • activates the held item Electric Seed, raising the holder's Defence by one stage • turns Nature Power into Thunderbolt
Grassy Terrain • grounded Pokémon receive 1/16 of their health back each turn • power of Earthquake, Bulldoze and Magnitude is halved • power of Grass-type moves increases by 50% • activates the held item Grassy seed, raising the holder's Defence by one stage • turns Nature Power into Energy Ball
Misty Terrain • protects grounded Pokémon from status conditions • power of Dragon-type moves is halved • activates the item Misty Seed, raising the holder's Sp. Defence by one stage • turns Nature Power into Moonblast
Psychic Terrain • prevents priority moves from being used (Shadow Sneak, Aqua Jet, etc.) • power of Psychic moves increases by 50% • activates the held item Psychic Seed, raising the holder's Sp. Defence by one stage • turns Nature Power into Psychic
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