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Cootes Bog (East side of the bog after using Surf)

Toxic inflicts severe poisoning on the target with an 85% accuracy rate. The poison damage incurred follows a formula: N * x, where N initially begins at 1, and x is equivalent to 1/16 of the target's maximum HP (rounded down, but not less than 1). As a Pokémon remains badly poisoned, N increments by 1 each time it sustains damage from either Toxic or Leech Seed (meaning it may increase twice within a single turn if the Pokémon is afflicted by both). The Pokémon's poisoned status reverts to regular poison if it encounters Haze, switches out, or when the battle concludes. When a badly poisoned Pokémon successfully employs Rest, it is cleansed of poison; however, the N value remains unaffected. Consequently, if the Pokémon subsequently experiences damage from burn, Leech Seed, or poison, that damage will still be calculated as N * x, and the N value will continue to rise by 1 for each instance (though, if the Pokémon was initially poisoned with Toxic, the N value is reset to 1). Notably, Toxic has no effect on Poison-type Pokémon.