I'd like to think that Storyshift Chara's fight wouldn't have any magic or complex bullet patterns, but there would be a hybrid of the green and purple soul modes to visualize physical attacks/blocking. It'd be like traditional RPGs where you block, dodge, etc (CHARA used SLASH!) but because it's a fistfight Chara can just skip your turn if you're not fast enough. Because their attacks are physical, Chara can brake your bones or make you bleed to death, so even getting hit once can be deadly. If you manage to kill Chara without bleeding to death, fainting from pain or getting knocked out then you could maybe kill sans

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