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Between Terrain and Weather, we've got Electric, Grass, Fairy, Psychic, Water, Onion, Fire, Ground, and Ice covered. What are some other battlefield-based effects that could work for other types, or should Terrains/Weathers cover the others?
What about something that affects the states of mind of all Pokemon on the field? Dark (Sinister Mind?) could induce Taunt on all sides, Ghost (Terrified Mind?) could prevent switching, and so forth?
Other ideas?
