[thejeff]

Not too familiar with Agartha, but 2 Death is enough. 2D+Staff lets you summon Mound Fiends, who can summon Liches, which gets you Hats for 6D. Not enough for Tartarians, but I don't think anyone can summon Tartarians without a pretender, the Astral Rings or artifacts.

It's expensive if you want them in bulk, but 3D is enough for basic battlefield and ritual casting.