Slayer, berserker, butcher. Call them what you want.
The Felorc Slayer was even before the consumption of demon blood, bloodthirsty thugs that the orc society only accepted as gladiators or the like. The Shattered Hand was an exception.
After that, they became completely insane savages!
But in Outland's newly established society by their demon lord, they are now highly respected warriors in the ranks of the Fel Horde.
The majority of the still living Slayers come from the Shattered Hand Clan and besides the ritualistic mutilation and separation of ONE hand, they also removed the second one, because nothing more applies to these madmen than constant bloodshed.
Although the "Slayer" used to correspond to the rank of general, these comrades have little to do with tactical planning. The frontal attack is the highest of the tactical approaches, and the fastest to just continue to enjoy the carnage they can wage.
Update, 21.01.: Just updated the Pictures.