Sleep

The Sleep spell is a peaceful way to end a confrontation.

Spell Description
Whenever a caster requires a non-violent solution in order to avoid or quickly bring an end to a confrontation, this spell comes in most handy. Sleep causes the target, foe or not, to fall asleep on the spot, ending any kind of conflict in a peaceful manner. Originally (before Ultima VI), this spell affected whole groups of foes, but was subsequently refined to only affect a single, selected foe. Mass Sleep can now be employed to affect whole groups of enemies. A Sleep Field is another way to accomplish the same effect.

Blue potions fulfill the same purpose as the spell.