Spells: The Circle of Locking the Nine Gates, Dimensional Anchor, Private Sanctum, Summoning Sanctuary, Hallow, Dimensional Lock, Magic Circle Against Evil
Preparations: The spell is performed in a 100 diameter stone hemisphere located 1 mile undergound under an ocean in the material plane. A Private Sanctum and a Dimensional Lock cover entire hemisphere. All metal within 1 mile has been removed. Two Magic Circles against Evil (augmented with dimensional anchor) have been cast in preparation for the CoLtNG These have been surrounded by Hallowed ground and a Summoning Sanctuary. There is 10' gap between the hallowed ground under the CoLtNG and the hallowed ground surrounding it.
While inside the CoLtNG Dispater is prevented from summoning or calling allies and is effected by a dimensional anchor.
To leave the CoLtNG Dispater must succeed on two DC 115 will saves. Each time he fails these he takes 120 damage. To leave the Summoning Sancuary by any means Dispater must succeed on an opposed CL check with a -20 penalty. To physically enter the hallowed ground Dispater must succeed on a DC 123 will save.