Rasengan Shuriken is probably a nuke or bazooka, while the other rasengan is meant for close range. Btw, I wouldn't be too shocked if he just throws it at Kakuzu in the next episode and misses .... naturally shortly after they showed what happened in this episode before again for the first 2 minutes (followed by the opening) and stared at each other for like 1 or 2 minutes

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