Tomb of Night (5e Spell)
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Note: this is a fanmade update of the Shadowcaster class found in the Tome of magic. I claim no ownership of any of this content. This was made solely because no official content update for the Shadowcaster class has been released by Wizards of the Coast* '
Unnatural darkness hardens around your target, taking them completely
Target a single creature within range. A dark prison of shadows appears around the target. This prison is a wall, and blocks line of effect and line of sight. During each of its turns, the creature takes 3d6 cold damage and 3d6 necrotic damage.
During each of its turns, the target may attempt a constitution saving throw. On a success, it uses its action to break out of the prison. On a failure, it gains one level of fatuige.
If you have mastery of the Ebon Walls path, the save DC for the spell is increased by 1.