Boitatá

Amphibious. The boitata can breathe air and water.

Heated Body. A creature that touches the boitata or hits it with a melee attack while within 5 feet of it takes 3 (1d6) fire damage.

False Appearance. While the boitata remains motionless, it is indistinguishable from an ordinary tree trunk.

Multiattack. The boitata makes one tail attack and, if it can, uses its Fool's Fire.

Tail. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 3 (1d4 + 1) bludgeoning damage plus 3 (1d6) fire damage, and the target is grappled (escape DC 14). Until this grapple ends, the target is restrained, the boitata can automatically hit the target with its tail, and the boitata can't make tail attacks against other targets.

Fool's Fire (Recharge 5–6). The boitata uses one of the following effects.

Blinding Flames. When a creature that can see the boitata starts its turn within 30 ft. of it, the boitata can force it to make a DC 13 Constitution saving throw if the boitata isn't incapacitated and can see the creature.  On a failure, the creature is blinded until the end of the boitata's next turn.

Maddening Gaze. When a creature that can see the boitata starts its turn within 30 ft. of it, the boitata can force it to make a DC 10 Wisdom saving throw if the boitata isn't incapacitated and can see the creature. On a failure, the creature can't take reactions until the start of its next turn and rolls a d8 to determine what it does during its turn. On a 1 to 4, the creature does nothing. On a 5 or 6, the creature takes no action or bonus action and uses all its movement to move in a randomly determined direction. On a 7 or 8, the creature makes a melee attack against a randomly determined creature within its reach or does nothing if it can't make such an attack.