-- Like much of what GS says, it's open to interpretation what he means by Class of combat skin. We see only two types of combat armor worn by Warrior-Servants, for example (three if you include Legends).
--BTW was trying to work out the yield of some of the Halo WMDs and the NOVA bombs made me raise my eyebrows into orbit. They need a yield of roughly 1-10 PETAtons of TNT to do what they did in First Strike, and that's being super optimistic on energy delivery to the moon and planet. I see that's in the same range that someone else
calculated on Halopedia too
A less optimistic calculation would require about (gulp) a 1 exaton yield.
-- On the other end of destruction, the energy densities of human propellants doesn't look too unreasonable. I get about a 20% increase in power for a Halo M118 round versus a modern M118. (assuming a 174g projectile and 55g of propellant with composite case)