I would probably bring Be'lakor rather than Fatey, here, honestly. Guaranteed Invisibility on an Eternal Warrior body with a nasty combat statline (fleshbane, armorbane, AP2, I8, hurrah!) sounds right up this type of game's alley. Scraping another 50 points will be... rough, but at that point, it makes me consider whether or not the DP is the best choice to go with. You could probably take a Soul Grinder for a tougher mini (albeit more vulnerable to grav/haywire), since 4+ to "wound" on AV13 is like having T9. Kinda. Then you'd be able to spare points for a greater reward on the LoC, upgrade to Be'la, and patch up those Horrors to 11.
What sphinx of plascrete and adamantium bashed open their skulls and ate up their brains and imagination? Imperator! Imperator!