Thives are not too powerful that's why they did this ability, and it is a rouge a thief, so he needs ot know hwat he's getting or using... what they didn't think of were the carnage it can instill in one character who plans on dualling...
i know what can kick his butt: A monk. With quivering palm... it might take a couple of retries though
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Heya! It's just me, Bahamut!