Dominance. All creatures with an Intelligence of 4 or less are Charmed by the Alpha Rex and obey its commands.

Legendary Resistance (3/Day). If the Alpha Rex fails a saving throw, he can choose to succeed instead.

Multiattack. The Alpha Rex makes three attacks: one Bite, one Stomp, and one Tail.

Bite. Melee Weapon Attack: +12 to hit, reach 10 ft., one target. Hit: 33 (4d12 + 7) Piercing damage. If the target is a Medium or smaller creature, it is Grappled (escape DC 17). Until this grapple ends, the target is Restrained, and the Alpha Rex can't Bite another target.

Stomp. Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 14 (2d6 + 7) Bludgeoning damage.

Tail. Melee Weapon Attack: +12 to hit, reach 15 ft., one target. Hit: 16 (2d8 + 7) Bludgeoning damage and make a Constitution saving throw (DC 20) or be knocked Prone.

Beer Belch (Recharges 5–6). The Alpha Rex exhales noxious gas in a 60-foot cone. Each creature in that area must make a DC 18 Constitution saving throw or take 28 (8d6) Poison damage and be Poisoned for 1 minute. While Poisoned in this way, a creature has Disadvantage on saving throws. It may repeat this saving throw at the end of its turns, ending the effect on a success.

The Alpha Rex can take 3 Legendary Actions, choosing from the options below. Only one Legendary Action option can be used at a time and only at the end of another creature’s turn. The Alpha Rex regains spent Legendary Actions at the start of its turn.

Bludgeon. The Alpha Rex makes a Stomp or Tail attack.

Charge. The Alpha Rex moves up to its Speed without provoking Opportunity Attacks.

Spit. The Alpha Rex spits out one creature Grappled with its Bite. That creature is thrown up to 60 feet in any direction, taking 21 (6d6) Bludgeoning damage and landing Prone. If the thrown creature’s path is interrupted by another creature, that creature must make a Dexterity saving throw (DC 15). On a failure, that creature takes 14 (4d6) Bludgeoning damage, is knocked Prone, and the thrown creature stops moving.