I think they have a couple endings avalible, 1.naruto/sasuke dieing at the same time, ending the so6p blood feud (after madara/kabuto are beaten and war has pretty much ended) konohamaru or kakashi or tsunade is hokage. 2. naruto beats sasuke and is turned back to good to join with naruto and defeat madara (madara probably would join with the gedo mazu statue and be some super-powerful foe like aizen was in bleach) not sure what they'd do with sasuke if he lived after they beat madara/kabuto, naruto becomes hokage. (don't expect this next one to happen at all but iv imagined it myself) 3. oro overcomes kabuto's will when his edo tenseis are all defeated and he has to fight naruto (or whoever) one on one and orochimaru is either defeated or takes over a post-fight (with madara or naruto or whoever) sasuke, naruto fights new super-oro then possibly another fight later with gedomazu-madara.
Lol i like the third theory, something aboard those lines should happen