Special Equipment. Abbadon wields the following magic items; a ring of protection, a ring of hidden desire (see below), and a +3 flame tongue greatsword he calls Damnation.

Ring of Hidden Desire . This ring allows Abbadon to learn the deepest, darkest desires of his victims. As an action while wielding the ring, Abbadon can target one creature he can see within 60 feet of him. The chosen creature must make a DC 20 Wisdom saving throw. On a failure, Abbadon immediately knows the target's darkest desire. On a success, Abbadon learns nothing, and the target is immune to the ring's effects for 24 hours. The ring can be used 3 times a day and regains all expended uses at midnight.

Preternatural Deflection. While wearing no armor and not wielding a shield, Abbadon's AC equals 13 + his Charisma modifier (included in the stat block).

Pride's Pursuit (3/Short Rest). Once per turn, if Abbadon misses a target with a weapon attack, he can immediately make another weapon attack against it.

Scourge (6/Short Rest). When Abbadon hits a creature with a weapon attack, he can choose to inflict upon it an insidious, lingering wound. The target must make a DC 20 Constitution saving throw. On a failure, the target loses 1d10 hit points at the start of its turn 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. The effect also ends if the target receives magical healing.

Spellcasting. Abbadon can innately cast the following spells, requiring no material components (Spell save DC 20, +12 to hit with spell attacks);

At Will: Eldritch Blast (4 beams), Minor Illusion, Blade Ward, Disguise Self

1/Day Each: Hex, Hellish Rebuke, Mirror Image, Crown of Madness, Hypnotic Pattern, Dimension Door, Mass Suggestion, Plane Shift, Bane, Dominate Monster

Legendary Resistance (3/Day). If Abbadon fails a saving throw, he can choose to succeed instead.

Multiattack. Abbadon makes two attacks with Damnation.

Damnation. Melee Weapon Attack. +12 to hit, reach 5 ft., one target. Hit: 12 (2d6 + 6) slashing damage plus 6 (2d6) fire damage.

Dissolute Dominion. Abbadon teleports to an unoccupied space he can see within 60 feet of him. All creatures within 10 feet of the chosen point must succeed a DC 20 Dexterity saving throw or take 16 (4d8) fire damage.

Bonds of Torment (6/Day). Abbadon conjures spiked chains that lash out against a creature he can see within 30 feet of him. The targeted creature must make a DC 20 Dexterity saving throw. On a failure, the target takes 24 (8d6) piercing damage and is restrained. While restrained in this way, a creature cannot teleport or use interplanar travel and takes 9 (3d6) piercing damage at the start of its turn.

As an action, the restrained creature can make a DC 20 Strength (Athletics) or Dexterity (Acrobatics) check. On a success, the creature escapes and the chains disappear. A creature that succeeds on the initial saving throw takes half damage and is not restrained.

Pernicious Spike (4/Short Rest). Melee or Ranged Spell Attack. Reach 5 ft. or range 30 ft., one target. Hit: 9 (3d6) poison damage, and the target must succeed a DC 20 Constitution saving throw or be poisoned for 1 minute. The target can repeat the saving throw at the start of each of their turns, ending the effect on themselves on a success.

Parry. Abbadon adds 3 to his AC against a melee attack that would hit him. If the attack does not hit, Abbadon can then make a melee weapon attack against the attacker. Abbadon must be able to see the attacker and be wielding a melee weapon to use this ability.

Abbadon can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature's turn. Abbadon regains expended legendary actions at the start of his turn.

Damnation. Abbadon makes a Damnation attack.

Eldritch Blast. Abbadon casts Eldritch Blast.

Bonds of Torment (Costs 2 Actions). Abbadon uses Bonds of Torment, if available.

Summon Fiend (Costs 3 Actions). Abbadon magically summons a fiend of challenge rating 8 or lower. The fiend appears in an unoccupied space within 60 feet of Abbadon. The fiend is friendly towards Abbadon and obeys his spoken commands. The fiends remains for 1 hour or until it is reduced to 0 hit points. Once Abbadon has used this legendary Action, he cannot use it again until he has completed a long rest.