I do not like the idea of the: demonic chaingun, demonic shotgun, demonic chainsaw, demonic plasma gun, demonic...
This doesn't give any climate to the game, it just give a weapon different name and stats, that all. To me, demonic weapons shouldn't even look like human weapons. A good example would be the "Hell Staff". Or any weapon that would have some "chaotic" nature:
"Soul devourer"
Sword that has a high chance to be found in Hell's Forge. Although it deals lower damage than the chainsaw (4d5) it has a chance of 10% to kill instantly anything it just touches
"Leacher"
Another sword. If player has high health, this sword drains his life to deal greater damage to the enemies. However health is drained whether you hit the enemy or not.
"Spitter gun"
A true chaotic weapon. BFG of the chainguns. Spits bullets in a conical shape. Once you pull the trigger 15 bullets start ripping your enemies. The only minus is that it takes 2 seconds to use. For demons it is only 1 second.
"Corrupter"
Looks like Hell Staff, but has one important feature. It corrupts you and turns you slowly to a daemon. After turning to a daemon you can use the demonic weapons without any penalties. But it is harder for you to use human weapons.
Oooops, looks like we have created a new game [;