Sandwyrm

Multiattack. The sandwyrm makes one Bite attack, one Gore attack, and one Stinger attack.

Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one creature. Hit: 12 (2d6 + 5) piercing damage.

Gore. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 11 (1d12 + 5) piercing damage.

Stinger. Melee Weapon Attack: +8 to hit, reach 10 ft., one creature. Hit: 9 (1d4 + 5) piercing damage, and the target must make a DC 15 Constitution saving throw, taking 14 (4d6) poison damage on a failed save, or half as much damage on a successful one. If the poison damage reduces the target to 0 hp, the target is stable but poisoned for 1 hour, even after regaining hp, and is paralyzed while poisoned in this way.

Spine Trap. When the sandwyrm is burrowed just below the surface of sand with its back spines exposed and a Medium or smaller creature enters the spines' space, the sandwyrm closes the spines on the creature. The creature must succeed on a DC 15 Dexterity saving throw or be restrained. When the sandwyrm moves, a restrained creature moves with it. The sandwyrm can have only one creature restrained at a time. A creature, including the restrained creature, can take an action to free the restrained creature by succeeding on a DC 15 Strength check.