Predatory Fungus
The fungus in this chamber detects the presence of trespassing creatures, but waits until they seem to be distracted before it strikes.
Euphoric. Any adventurers approaching within 20 feet of the fungus make a Charisma saving throw or become charmed by the fungus for 24 hours. Charmed PCs cannot contribute to group checks against the predatory fungus.
Fire Vulnerability. The use of any attack, effect, or spell that deals fire damage grants that adventurer advantage on checks against the predatory fungus.
Leave It Be. If the adventurers fail to recognize the fungus as a potential source of danger they become easy prey, triggering a critical failure.
Realize Danger. Any adventurer that makes a Nature check realizes the nature of the fungus and its effects.
The fungus might be dangerous, but it isn’t smart—the party can make a group Survival check to accurately and safely avoid the fungus and its hallucinogenic spores.
Critical Failure: Hallucinations drive the adventurers off course, losing 8 (2d4+3) hours of travel time. Additionally, each adventurer takes 22 (4d10) poison damage as the fungus takes root in their skin.
Failure: The adventurers escape the fungus, but lose 4 (1d4+2) hours as mild hallucinations lead them off course.
Success: The adventurers avoid the fungus, although they do not manage to destroy it.
Critical Success: The party thoroughly destroys the fungus and neutralizes the spores. These spores induce temporary euphoria, reducing each adventurer’s strife by 1.