Cobrasaurus

Pounce. If the cobrasaurus moves at least 30 feet straight toward a creature and then hits it with a claw attack on the same turn, that target must succeed on a DC 15 Strength saving throw or be knocked prone. If the target is prone, the cobrasaurus can make one bite attack against it as a bonus action.

Bite. Melee Weapon Attack: +7 to hit, reach 10 ft., one creature. Hit: 11 (2d6 + 4) piercing damage. The target must make a DC 15 Constitution saving throw, taking 24 (7d6) poison damage on a failed save, or half as much damage on a successful one.

Claws. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) slashing damage.

Euphoria Breath (Recharge 5–6). The cobrasaurus exhales a puff of euphoria gas at one creature within 15 feet of it. The target must succeed on a DC 14 Wisdom saving throw, or for 1 minute, the target can’t take reactions and must roll a d6 at the start of each of its turns to determine its behavior during the turn:

1–4. The target takes no action or bonus action and uses all of its movement to move in a random direction.

5–6. The target doesn’t move, and the only thing it can do on its turn is make a DC 11 Wisdom saving throw, ending the effect on itself on a success.