Abyssal Rift

Abyssal rifts function as the gate spell (CL 20th) used for planar travel, and are generally about 5 feet in diameter but can be smaller or larger. For 1d6 minutes before a rift opens, the air and ground thrum and vibrate with magical energies—a successful DC 29 Knowledge (arcana or planes) check, allows a character to correctly deduce that a rift is about to open.

Once a rift opens, it remains open for 3d6 rounds before closing. Sometimes a rift’s orientation can cause landslides, create whirlpools, or even create a pit-like obstacle. It could also allow dangerous Abyssal denizens to stumble through and become trapped within the Material Plane. A rift could even open inside an Abyssal sea (creating a sudden flood), within the heart of an Abyssal volcano (creating an unexpected surge of lava), or worse.

Casting dimensional anchor, dimensional lock, dispel chaos, or dispel evil on a rift’s location can prematurely close it.