Unless they pull another "Ragnarok is an Axe now", I can see a few names for DRK weapon(s). But I mean, Ragnarok, Liberator, and Apocalypse are all taken already cause foresight.

Ascalon, Arondight, Caladbolg, Nightfall, Aettir, Epeolatry, Valhalla, Gram, Vigilante, Ogrenix(Organics w/e), Defender.

Chaosbringer and Deathbringer are also possibilities.