Well, I do know that guardians have powers, but they barely wear any armor, excluding titan. So chief takes any weapon, easily kills the Guardians, then guns their ghosts. Now if you put him up against a titan, well they don't have the reflex of a spartan, and we'll use master chief at his peak in halo 3 (in my opinion). The titan at his peak, using the flaming hammer, he powers up, and then master chief pulls out a bubble shield and/or invisibility, Master chief then takes a plasma grenade, and sticks the titan.