Barbaratops

Brutal Critical. When the triceratops scores a critical hit, roll one of the dice an additional time and add it to the extra damage.

Danger Sense. The triceratops has advantage on DEX saving throws against effects that it can see while not blinded, deafened, or incapacitated. 

Freedom of Movement. The movement of the triceratops is unaffected by difficult terrain, and spells and other magical effects can neither reduce its speed nor cause the triceratops to be paralyzed or restrained.

The triceratops can also spend 5 feet of movement to automatically escape from nonmagical restraints, such as manacles or a creature that has it grappled. Finally, being underwater imposes no penalties on its movement or attacks.

Primal Strike. The weapon attacks of the triceratops are magical.

Protection from Poison. The triceratops has advantage on saving throws against being poisoned.

Rage (3/day). As a bonus action the triceratops can enter a rage for up to 1 minute (10 rounds).

It gains advantage on STR checks and saving throws (not attacks), +2 melee damage with STR weapons, and resistance to all damage except psychic.

Its rage ends early if it is knocked unconscious or if its turn ends and it hasn't attacked a hostile creature since its last turn or taken damage since then. It can also end its rage as a bonus action.

Reckless Attack. When the triceratops make its first attack on its turn, it can decide to attack recklessly, giving it advantage on melee weapon attack rolls using STR during this turn, but attack rolls against it have advantage until its next turn.

Regenerate. The triceratops regains one hit point at the start of each of its turns.

Relentless Endurance (1/day). When the triceratops is reduced to 0 HP but not killed, it can drop to 1 HP instead.

Trampling Charge. If the triceratops moves at least 20 feet straight toward a creature and then hits it with a gore attack on the same turn, that target must succeed on a DC 13 Strength saving throw or be knocked prone. If the target is prone, the triceratops can make one stomp attack against it as a bonus action.

Water Breathing. The triceratops can breathe both air and water.

Water Walk. The triceratops can walk on water as if it were a solid surface.

Wind Walk. The triceratops can spend one minute, during which time it is incapacitated and can’t move, to turn into a wisp of cloud. While in this cloud form, it has a flying speed of 300 feet and has resistance to damage from nonmagical weapons. The only actions it can take in this form are the Dash action or to revert to its normal form. Reverting takes 1 minute, during which time it is incapacitated and can't move.

Extra Attack. The Triceratops makes two attacks.

Gore. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 24 (4d8 + 6) piercing damage or 26 (4d8 +8) piercing damage while raging.

Stomp. Melee Weapon Attack: +9 to hit, reach 5 ft., one prone creature. Hit: 22 (3d10 + 6) bludgeoning damage or 24 (3d10 + 8) bludgeoning damage while raging.