Cheap way to kill SCs?

[Norfleet]

Because actual horrors, even if you can afford them, are expensive, and do not provide that much more benefit over false ones for their cost. Real horrors require an actual mage to be there, and pay slaves, and risk being eaten myself, or ritually cast and send one, for more slave cost.

False Horrors, on the other hand, can be performed with Caelum's natural air magic, have low fatigue cost, and given that neither will effectively kill a decent SC, you can just bury him in crap.