A transparent bubble of force appears around you, preventing anything from getting in or out.

Daily   ✦     Arcane, Conjuration, Force
Minor Action      Personal

Effect: You create a globe of force around you that lasts until the end of your next turn. Whenever you move (including teleportation), the globe moves with you. You cannot gain line of effect to any target other than yourself, and no creature or effect can gain line of effect to you. The globe doesn't block line of sight. It blocks objects and creatures attempting to pass through it.
The globe, although impenetrable, is not impervious to damage. Attacks against the globe automatically hit, and it has 100 hit points.

Sustain Standard: The globe persists.

Published in Arcane Power, page(s) 111.