Enrage (Recharges After a Short or Long Rest). When the espinas hit points drop below half of its maximum, it enrages for 1 minute. While enraged, the espinas AC is increased by 2, it has advantage on melee attack rolls, and loses its resistance to bludgeoning damage.

Light Sleeper. The espinas gains a +5 bonus to its passive Perception while it is naturally asleep. Sounds louder than a whisper within 10 feet of the espinas awaken it, if the creature making the sound fails a DC 19 Stealth check using the appropriate ability score.

Soft Hide. The espinas has resistance to bludgeoning damage while it is not enraged.

Multiattack. The espinas makes one Bite attack and one Tail attack.

Bite. Melee Weapon Attack. +7 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) piercing damage

Horn. Melee Weapon Attack. +7 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) piercing damage. If the espinas moved at least 20 feet straight toward the target immediately before the hit, the target takes an extra 14 (4d6) piercing damage. If the target is a creature, it must succeed on a DC 15 Strength saving throw or be pushed up to 10 feet away and knocked prone.

Tail. Melee Weapon Attack. +7 to hit, reach 10 ft., one target. Hit: 15 (2d10 + 4) piercing damage.

Blight Breath (Recharge 5-6). The espinas exhales a fireball at a point within 60 feet of it. Each creature in a 10-foot radius sphere centered on that point must make a DC 14 Dexterity or Constitution saving throw. On a failed save, a creature takes 16 (3d10) fire damage plus 10 (3d6) poison damage and is poisoned for 1 minute. On a successful save, a creature takes half as much damage and isn't poisoned. A poisoned creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.