Wand of slowing
|A magical device which slows down the actions of a targeted creature.|
Using a wand of slowing will attempt to slow a single target for several turns, making its movement and attacks take 1.5× as long as normal. This makes it much easier to escape them, and significantly reduces their damage output in combat. This effect has to overcome the target's magic resistance to succeed, but having a high Evocations skill will increase your odds of success.
Wands of slowing were removed in 0.20.