Weird

9th-level Illusion
Casting Time: 1 action
Range: 120 feet
Components: VS
Duration: 1 minute

Drawing on the deepest fears of a group of creatures, you create illusory creatures in their minds, visible only to them. The illusion calls on the creature's deepest fears, manifesting its worst nightmares as an implacable threat.

Targets. All creatures within a 30-foot-radius sphere centered on a point of your choice within range.

Save Negates. All targets affected by the spell must make a Wisdom saving throw. The creature takes 10d10 psychic damage. on a failed saving throw, or half as much on a success.

Ongoing Effect. If a target fails the saving throw, they have disadvantage on attack rolls and ability checks for the duration. At the end of each the creature's turns, they must make a Wisdom saving throw. On a failure, they take 5d10 psychic damage. On a success, they take half the damage and the spell ends.

At Higher Levels. The damage increases by 1d10 for each slot level above 9th.

Source: PHB 288, SRD

Changelog

Removed concentration requirement.
Altered damage so it now does half damage on a successful save, and the creature is incapacitated until the end of its next turn when the spell ends due to a successful save.
Added upcasting option.
Increased initial damage to 10d10 and secondary damage to 5d10, and does half damage on a success. Now bypasses frightened immunity. No longer incapacitates after a successful save.