Ick, sorry, this is... dreadful, and certainly no Doom I care about.
This is something Norman Osborne would do to gain power, not Doom.
This is simply murder and Doom would be above such things. If Doom wants magical power, he will gain on HIS terms, not as the result of barter with netherdemons!
Oh, and this is proof, if Secret Wars weren't enough, that any attempt to update the Classic Doom armour is instantly doomed to failure (no pun intended)