As an action, shadowy tendrils erupt from you, battering creatures. Each creature other than you in a sphere centered on you must make a Reflex saving throw.
On a failure, it takes 4d4 necrotic damage, moves at half speed, and can’t take reactions until the end of its next turn.
On a critical failure, it takes twice as much damage.
On a success, it takes half as much damage.
On a critical success, it takes no damage.
Additionally, until the end of your next turn, any bright light in the area is reduced to dim light.
Augment
You can increase the damage by 3d4 for each additional mana expended.
You can expend 1 additional mana so the shadowy tendrils continuously batter creatures around you. The duration changes to 1 minute/mana, concentration and the tendrils erupt around you in an aura shaped as a sphere. Until the spell ends, the aura moves with you, centered on you.
Whenever a creature enters the area for the first time on a turn or starts its turn there, it must make the Reflex saving throw. The damage is reduced to 1d4 and additional augments to the damage increase the damage by 1d4 for each additional mana expended, instead of the normal increase.
Shrouding Shadow. You can expend 1 additional mana if the tendrils continuously batter creatures around you so you and your allies in the aura are draped in deeper shadow. Creatures that rely on sight have disadvantage on attacks made against creatures draped in this shadow.