concentration, 1 minute/mana

As an action, you fill the air with spinning daggers in a 1-meter cube within 10 meters. A creature that enters the spell’s area for the first time on a turn or starts its turn there must make a Fortitude saving throw.

On a failure, it takes 3d4 piercing damage.

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.

Augment

You can increase the damage by 3d4 for each additional mana expended.