Reckless. At the start of its turn, the barlgura can gain advantage on all melee weapon attack rolls it makes during that turn, but attack rolls against it have advantage until the start of its next turn.

Running Leap. The barlgura’s long jump is up to 40 feet and its high jump is up to 20 feet when it has a running start.

Multiattack. Abolieth makes three attacks: one with its bite, fists and slam.

Bite. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. 2d4 Bludgeoning, 1d4 Piercing +6

Fist. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. 1d10 +6. 

Slam. Melee Weapon Attack: +10 to hit, reach 10ft., 2 targets in 10ft line range. 1d6 +6 Bludgeoning. Knock back 5ft, STR Save DC 16 or knocked prone.

Black Death. Must target creatures within Death Shroud. Spell Attack. +11 to hit, 3d6 Necrotic damage. 

Death Shroud (x2 Leg. Actions). Summons a shroud of magical darkness. Radius 20ft cube. Creatures who start their turn inside the shroud must make a CON Save DC 15 or take 2d6 Necrotic damage. half on a successful save.

Again (x1 Leg. Action). Abolieth makes an additional attack.

Call to Action (x3 Leg. Actions). Aboleith brings up to 5 fallen allies to 1hp within a 50ft radius (granted they would be effected by the spell revivify).

Pressure of Darkness. Abolieth gains double damage on inanimate objects. Non-magical items of size tiny or smaller immediately begin to shatter while within 10ft of Abolieth.

Exertion of War (x3 Leg. Actions). Abolieth lets out a war cry within a 30ft radius. Out to a 10ft radius CON Save DC 14 or stunned until the end of the creatures next turn. Out to 30ft CHA Save DC 10 or frightened, creatures can roll to save against fear at the end of each of its turns.