Utakata or Onoki. I believe Pain needed all 6 bodies to fully incapacitate him? w havent seen the show in a while. If Utakata doesn't know what he's in for, though I'll find it pretty hard pressed for his tailed beast regeneration to fully negate C4 which would probably be the end/all/be/all for him if he doesnt wrap it up quickly. On that same line of thought, I feel as if one stray Tailed Beast Blast would leave Deidara in the same way, so probably depends on who gets first hit.