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Crucial Advice
Ranger Utility 2

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

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.

Crucial Advice is an encounter power available to rangers at 2nd level.[PH:106]