Sucker Plant (5e Hazard)
From D&D Wiki
This Large plant grows vertically on walls. A Large or smaller creature who gets within 5 feet of it must make a DC 13 Dexterity save or get sucked up by the plant. A creature sucked up by the plant takes 2d6 poison damage and is then launched 10 feet, taking 2d6 bludgeoning damage.