When the target receives the Poison Card, their Hit Points immediately drop to 0 and they begin Bleeding Out. This is not true bleeding, but rather death by suffocation as their throat swells and closes off their airway.
The target cannot regain any Hit Points or stop Bleeding Out until they are Cleansed by an effect that would be able to remove the Envenomed condition, such as an Antivenom Poultice, Cleansing Touch spell, Antitoxin potion, or other similar effects.
The Kallahan’s Opus potion immediately ends all of the effects of this Poison.