You direct your ally's charge, allowing him or her to strike a deadly blow that pushes the foe backward.

Encounter   ✦     Martial
Immediate Interrupt      Ranged 10

Trigger: An ally within 10 squares of you charges a creature.

Target: The triggering ally

Effect: If the charge attack hits, the target gains a bonus to the damage roll equal to your Intelligence modifier, and he or she pushes the charged creature up to 2 squares. The target can then shift up to 2 squares to a square adjacent to the creature.

Published in Player's Handbook, page(s) 147, Class Compendium.