Sentinel of Light. Whenever an enemy kills an ally of Akshan within 100 feet of Akshan, Akshan will mark that enemy as a "Scoundrel". This mark lasts until the Scoundrel dies, a minute passes, or when Akshan dismisses the mark, requiring no action.

Divine Health. Akshan is immune to disease.

Great Radiance. Whenever Akshan hits a creature with an attack, that creature takes an extra 2d8 radiant damage. 4d8 is the target is a fiend or undead.

Cleansing Touch (7/day). As an action, Akshan can end a spell affecting him or a willing creature.

Holy Auras. All allies within 10 ft of Akshan gain the following benefits: they cannot be charmed, they cannot be frightened, and they gain a +7 to saving throws. These effects only last while Akshan is conscious. 

Purity of Spirit. Akshan is always under the effects of the protection from evil and good spell.

Legendary Resistance (3/day). Whenever Akshan fails a saving throw, he can choose to succeed instead.

Spellcasting. Akshan is a 15th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 20, +12 to hit with spell attacks). Akshan has the following paladin spells prepared:
Cantrips (at will): Spare the Dying, Sacred Flame
1st level (4 slots): Guiding Bolt, Heroism, Bless, Shield of Faith, Cure Wounds

2nd level (3 slots): Lesser Restoration, Magic Weapon, Aid

3rd level (3 slots): Beacon of Hope, Protection From Energy, Revivify, Daylight, Crusader's Mantle

4th level (2 slots): Freedom of Movement, Guardian of Faith, Death Ward

Multiattack. Akshan can take two shots with his Absolver twice.

Absolver. RangedWeapon Attack: +9 to hit, range 30/120 ft., 1 target. Hit: 22 (4d8 + 4) [radiant] damage.

Avengerang. Akshan throws out a boomerang in a 15ft long, 5ft wide line in front of him. Each creature in this area must make a DC 17 Dexterity saving throw, taking 18 (4d6+4) slashing damage, half on a success. As the boomerang comes back, they must make the saving throw a second time, taking 18 (4d6+4) slashing damage on a fail, half on success.

Avenged. If Akshan kills a Scoundrel within 1 minute of that Scoundrel killing an ally, Akshan can cast Revivify as a bonus action on that ally regardless of range, without expending a spell slot, or requiring material components. 

Akshan is a legendary creature and has 3 legendary actions. These legendary actions can only be taken at the end of another creature's turn, and Akshan regains all legendary actions at the start of his turn. 

Move (Costs 1 Action). Akshan can move up to his speed.

Attack (Costs 2 Actions). Akshan takes a shot with his Absolver or casts a spell that attacks only one creature.

Heroic Swing (Costs 3 Actions). Akshan fires off a grappling hook, swinging to a point within 30 feet of him in any direction. This movement does provoke opportunity attacks. Akshan can take an Absolver shot at each creature who takes an opportunity attack against him. This Absolver shot does not have disadvantage because of close quarters.