As an action, a creature that has moisture in its body that you can touch or see within 18 meters must make a Fortitude saving throw.
On a failed save, you siphon the moisture from its body as it takes 3d12 necrotic damage and 2 liters of water are removed from the creature. Unless it rehydrates, it can quickly become exhausted 1.
On a successful save, it takes half as much damage.
You can increase the damage by 4d12 for each additional mana or psi expended.