No Prep Time
Setting Akatsuki Hideout
What did Kabuto to groundbreaking again? He was powerful I admit, but I still think Pain murders him.
Depends on who you talk to. Some will say Kabuto managed to overwhelm Edo Itachi and EMS Sasuke. (both sides weren't trying to kill each other) if it weren't for Izanami. Technically Itachi died 3 times in the fight.
Some will say serious Itachi would have been enough if both sides were going for the kilk and Sasuke was a hindrance.
Its factual though Sasuke would have died more likely than not due to White Rage jutsu from Kabuto if it weren't for Sasuke in the initial start up.
Kabuto's prowess partially depends on location though. His abilities are better suited in an enclosed location, cave, forest, or places where there is less room to move about with lots of obstacles vs. an open field. Its not to say Kabuto is less deadly in an open field however.
Pain really lacks the ability to kill Kabuto though minus Human Path's soul rip or paralyzing with chakra rods. But Kabuto is quite much faster than any of the Paths.
Manda II > Cerberus.