Potpourri uses ToxicBurst on the party.
ToxicBurst is a Green enemy tech used in Chrono Cross. When Serge investigates Hydra Marshes in search of Hydra Humour to revive a poisoned Kid, he encounters several Potpourri. These stationary plants eject a virulent fume when their Hit Points reach a critical low, potentially causing the status effect Poison on party members and causing them to suffer low portions of damage.
To fend off predators, several plants release bursts of toxic fumes. This tech likely mirrors this natural defense mechanism.