You might reasonably think that the orcs of Middle-earth are, in general, warmongers. They quite clearly like to dive headlong into battle and kill people and burn and pillage and partake in all the parts of war that typically constitute mongering. But it turns out that there is a particular tribe of Orcs in the upcoming Middle-earth: Shadow of War that really enjoys the rough stuff. They are—you guessed it—the Warmonger Tribe.
The Warmongers bring fury, so the trailer says. They also bring doom. Additionally, they bring "a storm of terror, misery, and slaughter." And of course, they bring war. The upside is that they appear to bring war to their orcish cousins as much as anyone else, which by rights should enable the good guys to adopt a policy of containment and monitoring: Establish a defensive buffer, keep a tactical force prepped to plug the holes, and let the whole thing burn itself out.
You might think that doesn't sound very much in the keeping of Tolkien's heroes, but to that I say, have you checked out Shelob lately?
In any event, I'm sure you won't have to worry too much about all being quiet on the Mordor front: Joe recently gave Shadow of War's stealth mechanics a go and ended up murdering a battalion of Orcs and riding on the back of a dragon.
The Warmongers will presumably be the last of Shadow of War's Orcish tribes to be revealed. Warner has been rolling out a new one every couple of weeks—Terror, Machine, Marauders, Dark, and Feral—and the game will be out on October 10, which is a mere two weeks from today.