The enemy's warriors were originally to be Inferion. I'm pretty sure you've all seen the concept art. But if not, check here.
For a bit of background on them, they are the servants of the lord of fire. Fire, flame, inferno, fury...I tried to add all of words/aspects into the names and characters of the army. Inferion comes from "inferno" and "legion".
Now, some people think "Inferion" sounds too much like "inferior". I can agree with than, and while they are technically inferior to the players, it doesn't have the right ring to it once you think of it that way. :P
Another person suggested I simply change the "e" to "u". I like that a lot. For it makes "Infurian" sound the same, just with a "fury" connotation instead of an "inferior" one. This is an idea I had applied earlier to "Furian Phantoms" (mini-bosses).