Lovecrafting Atlantis.

[Poopsi]

with undead commanders it should work, but the idea was to make it on the lines of Pale Riders.

Making it a unit that, like the balrog, starts with some units in the battlefield, could work (assuming this is doable). Say, make it spawn four mannead-like units, with undead command, which start with some mandragora-like creatures as spawn...