15 way battle.
Scenario : the geonosian Colosseum.
EDIT: cut it down, to many people
Lets say somehow these 6 people got thrown in there and had to fight to survive.
Darth Nihilus
Darth Vader
Yoda
Darth Bane
Mace Windu
Qui gon
(and if you want to go the extra distance put the order of how you think they would be eliminated.)