Whirlipede (5e Creature)
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Medium monstrosity, any alignment
Speed Boost. The whirlipede's initiative count increases by 1 each turn it's in combat.
Charge. If the whirlipede moves at least 20 feet straight toward a target and then hits it with a steamroller attack on the same turn, the target takes an extra 7 (2d6) bludgeoning damage.
Steamroller. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 11 (2d8 + 2) bludgeoning damage.
Poison Point. If a creature hits the whirlipede with a melee attack, it can use its reaction to force the creature to succeed on a DC 14 Constitution saving throw or be poisoned for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on a success. If the saving throw is successful or the effect ends for the target, it is immune to the Whirlipede's Poison Point for 24 hours.