Avatar of Ubato

Divine Stride. While in the Labyrinth of Life, the Avatar cannot become lost, is unaffected by difficult terrain, and its speed cannot be reduced.
Legendary Resistance (3/day). If the Avatar would fail a saving throw, it can choose to succeed, instead.
Volcanic Retribution. Whenever a creature within 10ft of the Avatar hits it with a weapon attack, that creature takes 6 (1d10) Fire damage.

Multiattack. The tyrannosaurus makes two attacks: one with its bite and one with its tail. It can't make both attacks against the same target.

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 20). Until this grapple ends, the target is restrained, and the Avatar can't bite another target.

Tail. Melee Weapon Attack: +12 to hit, reach 10 ft., one target. Hit: 20 (3d8 + 7) bludgeoning damage.

Volcanic Breath. The Avatar spews from its mouth a line of flame and molten rock that is 60 ft long and 15 ft wide. Creatures in the line must make a DC 20 DEX save, taking 63 (18d6) Fire damage on a failure, or half as much on a success. Additionally, the space within the line becomes Difficult Terrain until the end of the Avatar’s next turn.

Look (1 Action). The Avatar makes a Wis(Perception) check.

Tail (1 Action). The Avatar makes a Tail attack.

Bite (2 Actions). The Avatar makes a Bite attack.

Volcanic Breath (4 Actions). The Avatar immediately recharges and uses its Volcanic Breath ability.