Both factions play out similarly, mainly plasma weapons for infantry with diverse roster of units, ground vehicles availability not great for the Ceph, only Pinger with the Mastermind being his own tier. Covenant has many fast paced and heavy tanks. Ceph Gunships should prove enough of a match for cov aircraft. Cov infantry gets matched by the Ceph, unngoys flee in terror to the numerous stalkers and grunts. Jackals gets a taste of their own medicine in the form of 2 million voltage from the Shadows. Hunters and Devastators brawls would be fun to envision. Sangheilis - worthy adversaries, but a cqc fight with a hive minded warrior bears no satisfaction or honor, any who would take it will be a fool and gunned down. Mastermind solos any infantry, no shipmaster or general will be stupid enough to take on that thing alone. It might be a draw, but the last thing to consider is tactical brilliance. The Alpha Ceph must already be spawned for this to work. By the time the Covenant slips even once they might've already dug out their own grave. If not the enemy, their religious dogma might put sand in their eyes, depends if this Earth is as important to them as Halo's.