With expert timing, you deflect an enemy's attack so that it misses you or your ally and targets another foe instead.

Daily   ✦     Martial
Immediate Interrupt      Melee 1

Trigger: An enemy adjacent to you targets you or an ally with a melee attack.

Target: The triggering enemy

Effect: Choose a different creature within the target's reach. The target now attacks that creature instead.

Published in Dark Sun Campaign Setting, page(s) 40.