D&D: Spawning Grounds

As the Blood War reignites throughout the Multiverse, the Archdevil Bel, has sponsored the creation of a new method for devils to return to the Prime Material Plane. Since fiends are unable to be summoned for 100 years after being destroyed on the Prime Material Plane, a hellbound Wizard named Karza has created a method to circumvent that limitation. 

Karza has been able to utilize the malignance of unhallowed places to physically birth a fiend into the Prime Material Plane, even if they are unable to be summoned. The process involves sewing Malediction Crystals in the selected area, where the fiend begins to physically grow over the course of 13 days. During the growth cycle, the Crystals not only allow the process to occur, but each crystal can transform into a Shard Devil to protect the fiend growing within the Spawning Ground.

While only one fiend may be "born" in a Spawning Ground at one time, the area may be used more than once (2d6 times before it ceases to become unhallowed ground).