* Calm is basically a crowd controlling effect. Such effects are exceptional for combat in high difficulty games.
* Calm Humanoid is a useful spell when you need to do some unfriendly things to NPCs but don't want to kill them. One such trick is to steal an NPC's armor by casting [[Morrowind:Disintegrate Armor|Disintegrate Armor]] on them until it breaks, casting Calm to remove them from combat, then finally pickpocketing the broken armor.
* On normally hostile targets, expect them to re-enter combat once the Calm spell has expired.