Out of their armor, a fourteen year old male SPARTAN-II (the Chief) accidently killed two full grown, battle-hardened ODSTs with his bare hands. The other two only received life threatening injuries. Accidently. They have 20 millisecond reaction speeds (ten or fifteen times faster than a normal person), with NO armor on, which decreases even more when outfitted and supported by an AI. When in combat, their reaction and decision times are so fast they experience time in slow motion. Their bones were enhanced with ceramics and re-ossification after puberty, and are virtually unbreakable. Their muscles basically never experience exhaustion, and are stronger and faster than any normal person's. The Chief once sprinted 65 mph for a short distance. They can easily lift over one thousand pounds. They are genetic masterpeices - the Chief is 6'10, 290 pounds without his armor on. Once, a SPARTAN killed a Brute with a one uppercut. Another ripped a Hunter apart with its bare hands. Kelly broke an Elite's wrist and cut its two partners in half with a single energy sword swing. The Chief once dodged an incoming missile strike by [i]slapping the missile away at the last second.[/i] This doesn't even take into account the formal combat training and experience of SPARTANS. The II's have spent decades in non-stop warfare, destroying entire fleets of Covenant and saving trillions of lives on their own. They are notoriously hard to kill and willing to do anything to win. Each one is a tactical genius. They grew up together. When working as a team, they basically read each other's minds. Each of them have specialities, and they dynamically and expertly change their tactics for any situation. SPARTANS don't give a crap about silly space magic.