True, but no one ever busts out their most powerful Jutsu right off the bat. I'm leaning toward the combined efforts of the Sannin. Well, except maybe Orochimaru, Kabuto, and MS Obito.Pein Rikudo ends this with Chibaku Tensei.
Proving me wrong is near impossible with actual manga feats.
Pain wins, all of Konoha posed no challenge. Jiraya was dead, Tsunade near dead, Oro can't handle the paths
Jiraiya starts in SM.
Oro has no Edo Tensei but has his hands.
Tsunade has no Byakagou.
I say Orochimaru solos, if not him and Jiraiya win without Tsunade.