Alghoul

Pack Tactics:  The Alghoul has advantage on attack rolls against another creature if at least on of the attacking creatures allies is within 5 ft. of the target  creature and the isn't incapacitated

Prickly. Any creature that makes a melee weapon attack against the Alghoul must make a DC 14 Dexterity saving throw, taking 5 (1d6+1) piercing damage on a failed save or half as much on a success 

Bloodrage: When the algoul falls below half of its maximum hit points, it enter frenzy, its spikes grow bigger and it's attack becoming more wild. It suffers a -2 penalty to attack rolls but gains +5 bonus to damage rolls, and its prickly trait instead deals 8 (2d6+1) 

Weakness: Shattering Spines.  If the Alghoul fails a saving throw against the spell thunderwave . its body´s spines shatter off, taking 1d4 to grow back. Until the spines grow back the Alghoul cannot benefit from its Prickly trait

Bite. Melee Weapon Attack: +2 to hit, reach 5 ft., one creature. Hit: 9 (2d6 + 2) piercing damage.

Claws. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 7 (2d4 + 7) slashing damage. If the target is a creature other than an elf or undead, it must succeed on a DC 10 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Piercing Shriek (Recharge 6) The Alghoul emits a mind-shattering wail, forcing all creatures within 30 feet of it that can hear it  to make a DC 14 Constitution saving throw. On a failed save, a creature takes 4 (1d6) Psychic damage and are stunned until the start of the Ghouls next turn. A creature can repeat the saving throw at the beginning of their turn , ending the condition on a success