You extend the invisible field of protection granted by your swordmage warding to a nearby ally.

Encounter   ✦     Arcane, Teleportation
Immediate Interrupt      Close burst 5

Trigger: An ally within 5 squares of you is hit by an attack that targets AC

Target: The triggering ally in the burst

Effect: You teleport to a square adjacent to the target. The target gains a +4 power bonus to AC until the end of your next turn.

Published in Manual of the Planes, page(s) 144.