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When a Pokemon receives sixteen (16) or more damage from a single attack, its Confusion Stage is lowered to 0; this means that the Pokemon snaps out of confusion when it moves next.
Since overheat did 18.5 damage, chansey would have snapped out of confusion before the end of the round
You know that one deal we proposed involving Smoochum and Klang?
Think you'd be willing to take a Piplup like you originally wanted? I have the CC for it now thanks to the Arcade (although I now want Audino to die terrible, terrible death at the hands of a CS Jirachi...)
You know, considering that a reroll would've been illegal, it's gone past noon, and the fact that I refreshed that page first, that can roughly be described as "Fail".