A nation the AI could use *well*

[Twan]

If given mages able to cast them without booster, the AI may be very agressive with offensive rituals (live wolven winter, fires from afar, seeking arrow, far summons...), which may or not be a good point. A nation with some mages specialized in rituals (ie : immobiles but powerful) and huge gem income may be good for the AI (but dont know if it will recruit these mages if others are available).

AI use priest reanimation well (except it sometimes have problems to move hundreds undead chaff when all leaders don't have undead leadership).

ME Ermor is actually one of the nations it plays correctly (because of this and the d+s mages fulfilling the evocation condition, the AI mages will spam nether bolt/dart behind undead hordes once researched).