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How would you rank the terrain effects?
>Electric: Pokemon on the ground can't be put to sleep and have their Electric-type moves boosted by 50%.
>Misty: Pokemon on the ground can't be afflicted with non-volatile status conditions (Burn, Freeze, Paralysis, Poison, and Sleep) and take half-damage from Dragon-type moves.
>Grassy: Pokemon on the ground have their HP restored by 1/16 at the end of each turn, and have their Grass-type moves boosted by 50%. Earthquake, Bulldoze, and Magnitude have their power halved.
>Psychic: Pokemon on the ground can't be hit by priority moves and have their Psychic-type moves boosted by 50%.
Personally: Psychic > Electric > Misty = Grassy