As an action, you can create a vial of liquid that looks, smells, and tastes like a healing potion or other beneficial potion. However, it is actually poison. A detect magic or detect poison spell reveals its true nature.

A creature can drink the contents as an action, becoming affected. At the start of each of its turns for the duration, the creature must make a Fortitude saving throw.

On a failure, it takes 2d10 poison damage and is poisoned 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 and and the effect ends.

On a critical success, it takes no damage and the effect ends.

Augment

You can increase the damage by 3d10 for each additional catalyst expended.