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Why is Whimsicott in D rank?
IT can taunt things and it can be a darkrai lure and the set up lure
It can 2hKO M-ray upon switching too
252 SpA Whimsicott Moonblast vs. 0 HP / 0 SpD Mega Rayquaza: 218-260 (62.1 - 74%) -- guaranteed 2HKO