ᚨᛋᚲᛖᚾᛞᚨᛞᛖᛞ Vecna, the Whispered One

God of Lichdom (1/Day). When Vecna is reduced to 0 Hit Points, he regains all of his Hit Points and unlocks access to Mythic Actions.

Legendary Resistance (6/Day). When Vecna fails a Saving Throw, he can choose to succeed instead.

Magic Resistance. Vecna has Advantage on Saving Throws against spells and other magical effects.

Undying. If Vecna is slain, his soul refuses to accept its fate and lives on as a disembodied spirit that creates a new body for itself after 1d100 years. After this period of time elapses and the new vessel is formed, Vecna regains all of his Hit Points and becomes active again, appearing anywhere within 100 miles of where Vecna was orginally slain. 

Unusual Nature. Vecna doesn't need air, food, drink, or sleep to survive. 

Special Equipment. Vecna carries a magical knife called Afterthought. In the hands of any other creature, Afterthought is a +3 dagger that deals an extra 1d6 Necrotic damage on a hit. 

Magic Mastery. Venca has Advantage on Concentration checks, can Concentrate on up to 3 different spells at a time (when he takes damage he ends Concentration on one spell of his choice), and does not require any Verbal Components when spellcasting. 

Marked for Undeath. Marked for Undeath is a unique condition applied only by Vecna. Creatures afflicted with this condition receive Vulnerability to Necrotic damage and, when reduced to 0 Hit Points, are raised as a mindless Zombie under Vecna's control. 

Aura of Enervation. All creatures that start or end their turn within 30 ft. of Vecna must succeed a DC 27 Constitution Saving Throw or take 23 (4d10) Necrotic damage and receive 1 level of Exhaustion. Creatures who failed the Saving Throw by a 10 or lower also receive the Marked for Undeath condition. 

Uncanny Reflexes. Vecna can take 1 Reaction per turn.

Soul Regeneration. At the start of his turn, Vecna regains 30 Hit Points. If he killed another creature in his previous turn, then he regains an additional 30 Hit Points per creature slain. 

Multiattack. Vecna uses Rotten Fate, Flight of the Damned, or Spellcasting. He then makes three attacks using Afterthought or Eldritch Burst in any combination of his choice.

Afterthought. Melee Attack Roll: +16 to hit, reach 5 ft., one target. Hit: 21 (3d10+7) Piercing damage plus 11 (2d10+7) Psychic damage and the target must succeed a DC 27 Constitution Saving Throw or be Cursed, While Cursed, the target takes 10 (2d10) Necrotic damage and cannot regain any Hit Points. At the start of each turn, the afflicted target can repeat the save, ending this effect on a success. 

Eldritch Ray. Ranged Attack Roll: +16 to hit, range 120 ft., up to 3 targets within range. Hit: 43 (6d10) Force damage and the target receives Marked for Undeath. Miss: Make a separate attack roll against a different creature within 60 ft. of the original target. 

Rotten Fate. DC 27 Constitution Saving Throw: One target within 120 ft. that Vecna can see is engulfed by necrotic magic. Fail: 102 (8d10+50) Necrotic damage which is doubled against Cursed targets. Success: Half damage only. Failure or Success: A Humanoid killed by this ability rises as a Zombie under Vecna's control. 

Flight of the Damned (Recharge 4-6). DC 27 Wisdom Saving Throw: All creatures within a 120 ft. cone are assaulted by a flying torrent of spectral entities. Fail: 66 (8d10+20) Necrotic damage and the target(s) are Frightened for 1 minute. They can repeat the save at the end of each turn, ending this condition on a success. Success: Half damage only. 

Supreme Spellcasting. Vecna can cast the following spells below (Spell Save DC 27)

At-Will: Detect Magic, Detect Thoughts, Dispel Magic, Lightning Bolt (Level 8 version), Invisibility, Fly, Animate Dead (9th level version), Dimension Door, Contingency

3/Day Each: Chain Lightning (Level 7 version), Circle of Death (Level 7 version), Scrying, Plane Shift, Symbol,

1/Day Each: Dominate Monster, Globe of Invulnerability, Finger of Death (Level 8 version), Power Word Kill, Time Stop

Vile Teleport. Vecna teleports to any unoccupied space within 60 ft. Each creature within 15 ft. of Vecna after the teleport takes 10 (3d6) Psychic damage. Vecna regains 80 Hit Points for each creature damaged in this way. 

Summon Undead Legions (1/Day). Vecna summons up to 10 Undead whose combined Hit Point Maximum does not exceed 500. These Undead must also have a Challenge Rating of 22 or lower. These Undead appear in any unoccupied space that Vecna can see within 120 ft., and they roll their own Initiative. On their turn, they follow Vecna's direct orders, following his commands unquestioningly until they die. 

Dread Counterspell. Trigger: A creature within 120 ft. of Vecna casts a spell. Response: That creature must succeed a DC 27 Intelligence Saving Throw or the spell's effect is cancelled and the caster takes Psychic damage equal to twice the level of the spell cast. 

Vengeful Shield (1/Round). Trigger: A creature hits Vecna with a Melee Attack. Response: Vecna gains 20 Temporary Hit Points and the attacker takes 20 Necrotic damage.

Fell Rebuke. Trigger: A creature within 120 ft. deals damage to Vecna. Response: Vecna utters a fell word, dealing 19 (3d10) Necrotic damage to the attacker and Vecna teleports to any unoccupied space within 60 ft.

Vecna has 3 Legendary Actions, choosing out of the following options below. At the end of another creature's turn, he can use one Legendary Action. He regains all spent Legendary Actions at the start of his next turn.

Dirsrupt Life. DC 27 Constitution Saving Throw: All creatures within 60 ft. of Vecna. Fail: 68 (9d10+10) Necrotic damage and the creatures receive Marked for Undeath.. Success: Half damage only. 

Vecna's Gaze. DC 27 Wisdom Saving Throw: One creature within 120 ft. that Vecna can see. Fail: 37 (5d10) Psychic damage and the target is Frightened for 1 minute. This ability deals double damage against creatures who are Marked for Undeath. Success: Half damage only.

Spell Barrage. Vecna casts two spells. 

After activating his God of Lichdom trait, Vecna can use the following Legendary Sctions below. 

Speech of the Whispered One (2 Legendary Actions). Vecna utters a forbidden, terrible word. He casts Power Word Kill on up to 3 creatures of his choice at-will. 

Deathly Ascension (3 Legendary Actions). Vecna ascends to the ultimate incarnate of Undeath for 1 minute. While ascended, he gains 2 Actions, 2 Bonus Actions, regains all expended uses of Legendary Resistance, and can use Summon Undead Legions three times a day instead of once.