The quick uppercut is the easiest way to steal once you get the timing down. Hit Jump + Attack at the same time to do a quick uppercut, then hit jump and steal as quickly as you can. You'll knock them into the air, rise with them, then you'll jump momentarily to break out of the attack and lunge forward for a steal.
Just quick upper, jump, steal. Do it fast and you'll grab it with no hassle.
This is the fire demon item, right? Just equip a Short Sword, literally. It has a super fast recovery, and the lower damage gives you more chances to steal. I'd much rather hunt this than wait for the Efreet's hug-of-doom.
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