Siege Beetle (5e Creature)
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Huge beast, unaligned
Charge. If the beetle moves at least 20 feet straight towards a target and then hits it with a horn attack on the same turn, the target takes an additional 10 (3d6) damage. If the target is a creature, it must succeed on a DC 17 Strength saving throw or be knocked prone. If the target is prone, the beetle can make a stomp attack against it as a bonus action.
Siege Monster. The beetle deals double damage to objects and structures.
Horn. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 16 (3d6 + 6) piercing damage.
Stomp. Melee Weapon Attack: +9 to hit, reach 5 ft., one prone creature. Hit: 15 (2d8 + 6) bludgeoning damage.
Siege beetles are massive insects capable of breaking stone using their gigantic horns. They can be trained, and some armies use them as living siege weapons.