He's Lvl 4. Shooting at Lvl 20+s. Go into a new game, go patrol Russia and go down the stairs if you follow the road to the left. Down there are a pair of Lvl 18-ish Elite Hive guys. Shooting them as a Lvl 4 does NOTHING. Them shooting you is pretty much 1 to 2 shots and you're dead. What Iron Banner is is just a fancy version of the standard Crucible, except it promotes quitting when you're losing. Otherwise, there's no difference between fighting a Lvl 4 guy or a Lvl 24 guy.