In this installment of Card Killers is the Fungusaur! Appearing in multiple editions, it was first printed in Alpha and most recently popped up in 8th Edition.
Huge Plant, unaligned
Armor Class: 15 (natural armor)
Hitpoints: 22 (3d12+2)
Speed: 40 ft.
Str: 19 (+4) Dex: 10 (+0) Con: 15 (+2) Int: 6 (-2) Wis: 8 (-1) Cha: 4 (-3)
Damage Immunities poison
Condition Immunities blinded, deafened, frightened, paralyzed, poisoned
Senses: blindsight 60ft. (blind beyond this radius), passive Perception 9
Regenerative Growth. The Fungusaur regains 5 hit points at the start of its turn. If the Fungusaur takes acid or fire damage, this trait doesn’t function at the start of the Fungusaur’s next turn. The Fungusaur dies only if it starts its turn with 0 hit points and doesn’t regenerate. If the Fungusaur is reduced to 0 hit points and does regenerate, increase it’s total hit points by +5. If it gains +10 hit points in this manner, increase it’s hit dice by one.
Trampling Charge. If the Fungusaur moves at least 20 feet straight toward a creature and then hits it with a slam attack on the same turn , that target must succeed on a DC 18 Strength saving throw or be knocked prone. If the target is prone, the Fungusaur can make one stomp attack against it as a bonus action.
Bite. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 9 (1d10+4) piercing damage.
Slam. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 9 (1d10+4) bludgeoning damage.
Stomp. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 10 (1d12+4) bludgeoning damage.
The Fungusaur is a massive fungal creature from the Underdark, frequently sharing territory with Myconids. Vaguely sauropod in shape, their soft rubbery flesh allows them to fit through tunnels much smaller than one would expect a creature the Fungusaurs size to be able to pass through. The Fungusaur feeds on minerals leeched from the surrounding stone, so generally ignore other creatures.
When confronted by aggressive creatures a fungusaur tries to charge the largest creature and slam into it first, then follows up with bite attacks at standing targets and stomps against prone targets until all are dead. Fungusaurs lack the mind to feel fear, and their rapid regeneration means few but those prepared to fight them survive. Fungusaurs don’t eat those it kills, leaving their victims where they lay. Those familiar with the creatures sometimes lure enemies into confrontations with a Fungusaur, letting the creature do the hard work of killing them, then looting the bodies after the Fungusaur has moved on.