Scorpius Rex (5e Creature)
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Large beast, unaligned
Multiattack: The Scorpius makes two claw attacks or one claw and one bite
Bite. Melee Attack: +8 to hit, reach 5 ft., one target. Hit: 21 (3d10 + 6) piercing damage.
Claw. Melee Attack: +8 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 6) slashing damage.
Quill Smack. Melee Attack: +8 to hit, reach 10 ft., multiple targets. Hit: 16 (2d10 + 6) bludgeoning damage. Target must succeed a DC 16 Dexterity saving throw or take (1d6) piercing damage and (3d12) poison damage
Pounce. If the scorpius moves at least 30 feet straight toward a creature and then hits it with a claw attack on the same turn, that target must succeed on a DC 15 Strength saving throw or be knocked prone. If the target is prone, the scorpius can make one bite attack against it as a bonus action.
The Scorpius Rex is truly one ugly looking creature, so ugly that even their mothers don't love them. But, the Scorpius is a truly terrifying creature not because it is ugly, but rather because it is unseen during an attack. The Scorpius is unable to be fooled by the darkness of night or disguises, it tracks its prey through infrared vision, it sees its prey's heat signature rather than by typical sight. The Scorpius packs a very unique surprise if its prey does survive its initial attack, a deadly neurotoxin in its tail spines that is nearly 100% fatal in humans if not treated with medical intention, the toxin is quick acting and causes respiratory failure and eventually cardiac arrest. Larger creatures with tougher skin seem to fare better against the toxin, especially Sinoceratops, which seems to only get sleepy when envenomated, and can be cured if the spines are merely removed.