I would agree with you if this was current Halo vs current star wars but because OP included the ancient races, that makes for a HUGE gamechanger. That's why my vote goes to Halo as they have three factions that can take this all alone. star wars has awesome superweapons but these don't stand a chance against the Halo superweapons like the Halo's, shield worlds and star roads. Hell even forerunner fleets themselfs fit the superweapon category because their firepower and the ability to supernova a star.