As two actions, a plume of poison blooms at a point within 20 meters. The plume spreads around corners. Each creature in a sphere centered on that point must make a Fortitude saving throw.
On a failure, it takes 5d6 poison damage and is poisoned for the duration.
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.
A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
You can increase the damage by 2d6 for each additional mana expended.