Horror Marking as a battle tactic for a non-Blood nation

[thejeff]

In detail, I don't know.
But for practical experience, I had a prophet sufficiently marked in one SP battle that he attracted a Horror (not a Doom Horror) within a couple turns.

It probably works best in the early game. Most SC pretenders won't be kitted out
to deal with even regular horrors early on
If nothing else, it's a good psychological weapon. Is your enemy really willing to keep sending his pretender to get Horror Marked again and again? If it doesn't get him killed right away, but he gets pulled from the field that's probably good enough...