Rooter Amalgamation (5e Creature)
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Large plant, neutral evil
Saving Throws Con +5
False Appearance. While the rooter remains motionless, it is indistinguishable from an ordinary plant.
Fear of Fire. If the rooter takes fire damage, it has disadvantage on attack rolls and ability checks until the end of its next turn.
Multiattack. The rooter makes two melee attacks.
Vine. Melee Weapon Attack: +5 to hit, reach 10 ft., one target. Hit: 10 (2d6 + 3) bludgeoning damage. If the target is a creature, it must then succeed on a DC 13 Constitution saving throw or become infected with a disease. Creatures immune to the poisoned condition are immune to this disease.
Rooters continuously grow until they die, but some absorb other rooters when they grow, forming hideous monsters called amalgamations. They are stronger and hardier than other rooters, though no more intelligent, and they gather groups of rooters which they then use to storm settlements. The amalgamation is always at the head of such a surge, using its brute strength to destroy everything in its path. If one or more of the rooters that composed it was one of the few that had greater intelligence, could cast spells, or speak, the amalgamation retains all of those abilities, and might wield weapons or wear armour if one of its components did so.