Data from the "Eater of Gods" test:
Horror Attacked Commander Turns
Maker of Ruins 1 1 0
Eater of Gods 1 1 0
Eater of Gods 0 1 6
Eater of Gods 0 1 9
Eater of Gods 0 1 6
Maker of Ruins 0 1 24
Abomination of Desolation 0 1 68
Eater of Dreams 0 1 15
Maker of Ruins 1 1 0
Therefore (so far)!!! I am making a strategy recommendation that if you want to play with horrors, wish for "Abomination of Desolation" and
DO NOT cast "Gift of Reason" on it. More to come....
Wishing for Horrors is one of my favorite ideas.
I'm not going to bother wishing for the Eater of Dreams, since I find him kind of bleh compared to the Abomination of Desolation (even in standard unit form). I will try wishing for Scabiel, the Maker of Ruins, though... He would be the
bomb as a permanent standard unit.... Nope, wishing for Maker of Ruins works (apparently) like Doom Horror, Slave to Unreason, and Eater of Gods... You get one random horror. The same thing happens when trying to summon "Eater of Dreams"--random horror, possible attacks (I figured I'd try it once).
Apparently Hruvur is more friendly than the other horrors...
Therefore, I have settled on this:
Doom Horror, Slave to Unreason, Maker of Ruins, Eater of Gods, and Eater of Dreams are not as worthy of your pearls... They will allow you to summon a random horror, but you will be subject to attacks. Additionally, you will spend, on average, 7 or more pearls per turn to use the horrors.
Abomination of Desolation is an excellent wish and worthy of your gems, but your Abomination can be stolen in the same way that any unique unit can be, but turning him into a commander instead of a subordinate ruins your fun quickly.