Clethon, Death Unleashed

Speedy: Clethon, Death Unleashed can take two turns

Legendary Resistance 3/Day: If Clethon, Death Unleashed fails a saving throw, he can choose to succeed instead.

Flyby: Clethon, Death Unleashed does not provoke opportunity attacks when flying.

Amphibious: Clethon, Death Unleashed can breathe underwater.

Spellcasting. Clethon, Death Unleashed is a 20-level spellcaster. His spellcasting ability is Intellegence (spell save DC 25, +17 to hit with spell attacks). Clethon, Death Unleashed has the following Wizard spells prepared:
Cantrips (at will): Acid Splash, Fire Bolt, Minor Illusion, Poison Spray, Ray of Frost 
1st level (4 slots): Burning Hands, Charm Person, Chromatic Orb, Ray of Sickness                  2nd level (3 slots): Alter Self, Flaming Sphere, Gust of Wind, Scorching Ray                               3rd level (3 slots): Counterspell, Dispel Magic, Fireball, Vampiric Touch                                     4th level (3 slots): Greater Invisibility, Hallunctionary Terrain, Wall of Fire                                  5th level (3 slots): Cloudkill, Telekinesis, Wall of Force                                                                    6th level (2 slots): Chain Lightning, Disintegrate, Mass Sugestion                                                7th level (2 slots): Delayed Blast Fireball, Prismatic Spray                                                              8th level (1 slot): Incendiary Cloud, Sunburst                                                                                    9th level (1 slot): Shapechange, Wish

Multiattack: Clethon, Death Unleashed can take one Spiked Tail attack, one Clubbed Wings attack, and his choice of two Flame Axe attacks or two Poison Bow attacks. He can forfeit all of that for one cantrip and one other spell.

Spiked Tail: Melee Weapon Attack: +17 to hit, reach 15ft, as many targets within range of the tail (think in range of a tail sweeping; extends 15ft and continues for 10ft before stopping). Hit: 19 (2d10 + 8) [Piercing] damage.

Clubbed Wings: Melee Weapon Attack: +17 to hit, reach 20ft on either side of Clethon, as many targets within range of the wings (think of the wings beating; extending 20ft on either side of Clethon, Death Unleashed and move 5ft in each direction before stopping). Hit: 14 (1d12 +8) [Bludgeoning] damage.

Flame Axe: Melee Weapon Attack: +17 to hit, reach 5 ft., 1 target. Hit: 26 (4d8 + 8) [Slashing] + 11(2d10) [Fire] damage.

Poison Bow: Ranged Weapon Attack: +14 to hit, range 200/1000 ft., 1 target. Hit: 14 (2d8 + 5) [Slashing] + 11(2d10) [Poison] damage and the target must make a DC 18 Constitution save or be poisoned for 1 hour.

Deathly Summoning (1d20, Recharge on 20): Clethon, Death Unleashed, summons the spirits of fallen warriors to do his bidding. 1 vampire spawn, 1d3 wraiths, 1d4+1 ghosts, 2d4 wights, 2d6 wights and 3d8 zombies. The undead are all friendly to Clethon, Death Unleashed, and act on initiative 15. They follow Clethon, Death Unleashed's instructions, and if they have been given no orders, they act in self defense.

Clethon, Death Unleashed can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. Clethon, Death Unleashed regains spent legendary actions at the start of its turn.

Flight (Costs 1 Action). Clethon, Death Unleashed flies, walks, or swims up to twice his full movement without provoking opportunity attacks.

Shift (Costs 1 Action). Clethon, Death Unleashed teleports up to thirty feet and makes one melee attack .

Expelling Blast (Costs 2 Actions). Clethon, Death Unleashed screams. All creatures within thirty feet of him are thrown sixty feet away or until they hit a solid object. When they land, they take 1d6 damage for every 10ft they travel. If they can cast spells, they lose a first level spell slot, and Clethon, Death Unleashed gains a first level spell slot. If he hasn't cast any first level spells, he gains a second level spell slot, etc. If they cannot cast spells, half the damage that they take goes to healing Clethon, Death Unleashed.

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