Utter Dome

Area 
Protects against physical and magical attack; has the effect of a combination Force Dome and Pentagram. However, creatures cannot be summoned within it, and there is no marking to erase. Can only be removed by Dispel Magic or Counterspell. Resists any attempt to look through with magic. 
Like Force Dome, an Utter Dome takes a full second to form once cast.

Duration: 1 minute. 
Base cost: 6 to cast. 4 to maintain. 
Prerequisites: Magery 2, Force Dome, and Spell Shield.