I find that really hard to figure out. Kabuto indeed thought he was attacking Sasori, so Yamato's disguise wasn't broken, and we can probably assume the item he's looking for question wasn't fake. But if it's not, and if it's his reward for five years of spying, why doesn't he wait to get it before attacking Sasori?Originally Posted by Munsu
I can only think of two reasons, though I don't like either personally:
a) He thinks he can retrieve it from Sasori's corpse when they're done with him.
b) Whatever he needed, Oro gave him. (that just sounded kinda bad...)