Mario & Sonic Guy
Old rivalries live on!
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Cranky Kong
Cranky Kong has been stated to be Donkey Kong's ancestor and possible father. If he's an assist trophy, he'd be a chatter box, just like Mr. Resetti.
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Mr. Resetti
However, Cranky Kong wouldn't be completely useless. Anyone who gets too close to Cranky will get a taste of his walking stick. And trust me, the stick can be quite painful. Cranky will show various emotions during his chattering. This may also show how painful his walking stick can be.
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Cranky's Different Emotions (astonished, funny, surprised, confused, and angry)
Cranky will mainly talk about the old games back in the 1980's. He'll also taunt your foes by stating that the new games are WAY too easy than the classics.
Cranky would be one nutty assist trophy if he is ever made into one. Hopefully, his appearance in Brawl can bring back the old days.