Ghulgathganoon's Red Stone Slab
1,000 pounds 10 × 10 foot rock slab
touching the slab may give visions of the past at its location
Reading the spell upon the slab requires Primordial, and an Arcana check of 20. Anyone can use the spell once the check is passed and the reader understands Primordial.
The writting details the steps needed to summon the demon Ghulgathganoon (same as planar ally spell)
Ghulgathganoon requires payment of 100gp per minute for 10 minutes
1000 gp per hour for 24 hours
A human sacrifice per day for tasks up to 10 days
If Ghulgathganoon isn’t paid or acted upon aggressivley, he will attack or return to his plane of exsistance. He must touch the slab and use an action to return or otherwise be banished.