Arms of Hadar
Level 1 Conjuration (Warlock)
Casting Time: 1 Action
Range: Self (10 ft. )
Components: V, S
Duration: Instantaneous
Attack/Save: STR Save
Damage/Effect: Necrotic
Invoking Hadar, you cause tendrils to erupt from yourself. Each creature in a 10-foot Emanation originating from you makes a Strength saving throw. On a failed save, a target takes 2d6 Necrotic damage and can't take Reactions until the start of its next turn. On a successful save, a target takes half as much damage only.
Using a Higher-Level Spell Slot. The damage increases by 1d6 for each spell slot level above 1.