Venom
If a bite deals at least 1 damage, the target loses 1 additional HP at the end of each of the next 2 rounds; this effect does not stack.
Animal Challenge 2
A venomous snake hides under stones, among roots, in tall grass or in warm cracks in the rock. This bestiary entry represents a game creature with a venomous bite, rather than every snake in the real world. It usually lives alone, seeking prey and a safe shelter.
It is inconspicuous and can wait motionless for a long time. It generally does not attack a larger creature as prey; danger mainly arises when it is startled or cornered. The party should watch where it steps and reaches. Its game venom only takes effect after a bite that causes damage, and the subsequent effect is specified precisely in its ability.
A snake may guard a location simply because it has chosen to shelter there. Taking another route or leaving it room is often wiser than fighting. In a story, shed skin and small tracks might lead to a warm spring or a room that has remained unopened for years.

If a bite deals at least 1 damage, the target loses 1 additional HP at the end of each of the next 2 rounds; this effect does not stack.