Phantasmal Killer

You tap into the nightmares of a creature you can see within range and create an illusion of its deepest fears, visible only to that creature. The target makes a Wisdom saving throw. On a failed save, the target takes 4d10 Psychic damage and has Disadvantage on ability checks and attack rolls for the duration. On a successful save, the target takes half as much damage, and the spell ends.

For the duration, the target makes a ability=wis dc=@attributes.spell.dc saving throw at the end of each of its turns. On a failed save, it takes the Psychic damage again. On a successful save, the spell ends.

Using a Higher-Level Spell Slot. The damage increases by 1d10 for each spell slot level above 4.

Foundry Note

The associated Active Effect does not include changes to provide Disadvantage on attack rolls and should be handled manually.