Ebon Dome

A 30-foot opaque black dome is created on a point of the caster's choosing that they can see within 60 feet. Creatures within the dome must make a Dex save, according to the caster's Spell Attack, or a DC 15, whichever is higher. Creatures within the dome take 3d6 Force Damage, and half on a successful save.

Regardless of save, targets in the dome suffer 1/2 movement speed, and take 1d6 Force Damage if they begin their turn in the sphere, as the crushing atmosphere of the dome presses down on them. This damage cannot be resisted or reduced.

The sphere remains in effect for 3 rounds and is an opaque black color inside, negating all visual capability, including magical Darkvision/Truesight. Combatants inside the dome may still use Blindsight/Blindsense to negate Disadvantage when fighting within this space.

The caster can see inside the sphere and can dispel it early if necessary. The damage done by the spell increases by 1 per level above 3 that it is cast at. Eg: Level 3 is 3d6, Level 4 is 4d6, etc. The damage done at the beginning of a creature's turn within the sphere is likewise increased according to the Slot Level of the spell as it was cast. Eg: Level 3 is 1d6, Level 4 is 2d6, etc.