Demonic Fissure

Upon casting Demonic Fissure you tear a whole across the plains opening a portal to the Abyss/Circles of Hell. In doing so bring up to two Demons/Aberrations from those planes the CR for the entities has to be in the range of 25-26. After summoning both beings little demons follow suit (1/2-2 CR, Up to 10 Total) and are commanded by the two higher demons, You can control the things you summon and command them to do whatever you wish. However at the end of your turn you must make a Con Save to remain in control of said beings, On a failure you lose control and the DM takes control of the beings you summoned, On a successful Save you remain in control.

If the beings drop to 0 Hp they return to their home plain and can't be summoned again for 1 week, as they are regenerating their powers in their home