From NexusWiki

Blind is a spell cast by Mages which immobilizes an enemy for a period of 60 seconds. If a player is beside the enemy, it can still attack. Mages learn this spell at the 61st insight. To learn it, a Mage needs a dark amber, two ambers and 400 coins.

Aligned spell names are:

Kwi-Sin - Darken Veil

Ohaeng - Ice Glare

Ming-Ken - Winters Shadow