Ground wise....Covies. Ship to ship engagement....covies. Superweapons....Cabal It's really circumstantial. If the Cabal have enough time to deploy The Almighty, successfully defend it, and fire... maybe Cabal win. Unless the supernova disrupts the Covies ability to slipspace out of dodge... they'd just warp out. Though it only took one Guardian to stealthily neutralize The Almighty.... which Sangheili and Jiralhanae (probably butchered the spelling) are capable of. However if the Fleet (of Particular Justice) that took out Reach is present.... that would hasten the Cabal to nuke the hell out of the system. Without The Almighty present... I go with Covies.....do to sheer numbers. Though..we don't know too much about Cabal Ship shielding and Armor.... too make a truly accurate victor.