You are wise in all things. The sooner your friends realize this, the safer and better off they'll be.

Encounter   ✦     Martial
Immediate Reaction      Ranged 5

Trigger: An ally within range that you can see or hear makes a skill check using a skill in which you're trained

Effect: Grant the ally the ability to reroll the skill check, with a power bonus equal to your Wisdom modifier.

Published in Player's Handbook, page(s) 106.