Venom (5e Creature)
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Medium construct, chaotic evil
Damage Vulnerabilities lightning, thunder
Parasite. As an action, a venom can take over a sentient creature that knows at least one language and can use any natural weapons the creature has, such as a dragon's breath weapon. Also, that creature gains the venom's tendril attack. The creature can make a Strength saving throw to throw the venom off, DC equal to 14. If they fail, they are completely under control of the venom. If they succeed, the venom will be thrown off and will attack someone else. Also, the venom can use this as a reaction against someone who makes a melee attack against it.
Liquid Form. When not attached to a creature at all, it can pass through an area no smaller than an inch wide without squeezing.
Tendrils. Melee Weapon Attack: +5 to hit, reach up to 20 ft., one target. Hit: 5 (2d4) bludgeoning damage.
Slam (when attached to a creature with no natural weapon). Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) bludgeoning damage.
Slash (when attacked to a creature with no natural weapon). Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 7 (2d4 + 2) slashing damage.
Venom is a creature of immense power. When attached to a human, it makes a bulky, fighter-type body along with a white spider on the chest. It is always pitch-black though, for reasons beyond my understanding. Flair? Anyway, when it is separated from the host, it is a volatile creature that can take a crude humanoid shape that will not fool anyone if it even tried to sneak in anywhere like that. Most people sneak it in places in a small vial as it can grow as it takes over a creature. It can transform a humanoid creature's arms into that of swords of some kind of blunt instrument, but not a ranged weapon. It can make a ranged attacks only when the creature it takes over has a natural attack that is ranged or has a bow or something of the like. It attacks like an animal, simply attacking and hoping to kill whatever is irking it.