Aivoc's Hellfire Rift

You create a slow moving dimensional geyser of hellfire flame adjacent to you. The rift is 5ft in width, and 20ft long, and ejects hellfire to a height of 20ft. At the end of your turn, the rift travels 10ft. You can not choose a direction in which a creature is within 30 ft of you.

Any creature that enter the rift's space or start their turn there must make a Dexterity Saving throw. On a failure, they take 4d10 fire and 4d10 necrotic damage, half on a success. A creature that fails and is not flying falls 5ft into the rift, where it must make a Charisma saving throw, or be banished to the nine hells. A creature that is larger than the rift can not fall into it. The rift's space is difficult terrain, and can be climbed out of with simple movement.

At Higher Levels. For every 2 higher levels, the rift's width increases by 5 ft, and it deals 1d10 additional fire and necrotic damage.