C'Thun Servants (Qiraji, Silithids, Mummies, Tol'vir + Anubisaths): (undead + some zerg)
1) undead based, towers aura instead blight, part units living but self-explode & cheap
2) living (beetles) have a limit on the use of abilities, when it is exhausted and zero health = explode
3) no houses + max limit at start, summon around towers
4) living regen anywhere, undead regen hp-mana only from aura