As two actions, you coagulate the blood of a creature that you can touch or see within 10 meters. The creature must make a Fortitude saving throw. If the creature has no blood in its body, the spell has no effect on it.
On a failure, it takes 4d6 necrotic damage and is stunned 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.
Augment
You can increase the damage by 6d6 for each additional mana expended. If this spell is augmented to target additional creatures, this damage is halved.
You can target one additional creature for each additional mana expended. The creatures must be within 5 meters of each other when you target them.
You can expend 1 additional mana so the duration changes to 1 minute/mana, concentration and the creature is stunned for the duration. 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 expend 1 additional mana so the creature is paralyzed instead of stunned.