Archmage Sylric, King of Eldoria

Magic Resistance. Sylric has advantage on saving throws against spells and other magical effects.

Epic Boons. Once per day, Sylric can cast a spell without using a spell slot. He can use an action to escape from any magical or nonmagical restraints.

Special Equipment. Sylric wears a Robe of the Archmage. He also has a +3 Elven Curve Blade, a +3 Scimitar, and a +3 Buckler, a +3 Arcane Grimoire, and a +3 Wand of the War Mage (Staff)

Arcane Weapons. Sylric deals and extra 8d8 force damage whenever he hits with any nonmagical attack, and his weapons count as magical.

Spellcasting. Sylric is a 20th-level spellcaster. His spellcasting ability is Intelligence (spell save DC 33, +25 to hit with spell attacks). Once per day, he can cast a spell without using a spell slot.

Cantrips (at will): minor illusion, mage hand, shape water, mold earth

1st level (4 slots): detect magic, identify, mage armor, magic missile, fog cloud, silvery barbs (Spell Mastery), shield (Spell Mastery), absorb elements

2nd level (3 slots): detect thoughts, mirror image, misty step (Spell Mastery), vortex warp, invisibility

3rd level (3 slots): counterspell, fly, lightning bolt, fireball, animate dead, tiny servant

4th level (3 slots): banishment, fire shield, Polymorph, Sickening Radiance, Divination, greater invisibility

5th level (3 slots): cone of cold, scrying, wall of force, steel Wind Strike, hold monster, animate objects, telekinesis

6th level (1 slot): globe of invulnerability, contingency, magic jar, otto’s irresistible dance, scatter 

7th level (1 slot): teleport, Plane Shift, Fire Storm, Chain Lightning

8th level (1 slot): mind blank, Demiplane, Maze, Illusory Dragon, Dominate Monster

9th level (2 slots): Wish, True Polymorph, Shapechange, Gate, Meteor Swarm

Arcane Rejuvination. If Sylric is reduced to 0 hit points, his hit point total is reset to 300, he regains all of his spell slots, and he can use the options in the Mythic Actions section as legendary actions.

Regeneration. Sylric heals 20 hit points at the start of his turn. In addition, he can end one spell, condition, or effect that is currently on him. This ability does not function for 1 round if he takes necrotic damage. He only dies if he starts his turn without regenerating. If he dies, he gains a new body in 1d10 days. The body appears within 5 feet of Mystra, with all of his spell slots, hit points, and equipment.

Multiattack. Sylric makes four elven curve blade attacks, or four Arcane Blast attacks.

Elven Curve Blade. Melee Weapon Attack: +19 to hit, reach 5 ft., one target. Hit: 18 (3d6 + 8) slashing damage plus 36 (8d8) force damage.

Arcane Blast. Ranged Spell Attack: +25 to hit, range 360 ft., one target. Hit: 63 (12d8+9), and the target suffers one of these effects:

• It is knocked prone
• It is pushed back 10 feet
• It is stunned for 1 round (DC 17 constitution saving throw negates)

King of Eldoria. Sylric invokes the power of the land of Eldoria, transforming him into a Dragon, or back into an Elf. His statistics change as follows while in Dragon form:

• He become Gargantuan
• His creature type becomes Dragon
• He gains immunity to fire damage
• He gains the ability to breathe fire in a 120 foot cone. You can make the cone less wide by increments of 10 (5 from each side). It does 32d8 damage on a failed DC 20 dexterity save, or half as much on a successful one.
• He gains a 320 foot flying speed.
• He gains 750 extra hit points. When these are burned through, he can’t gain them again until he finishes a long rest, but he can still assume the form of the dragon with his regular hit points. If he reverts to his normal form earlier, the extra hit points go away until he becomes a Dragon again.
• His strength becomes 30, and his constitution becomes 30
• He gains the following actions:
  • Claw: +18, reach 10 feet. Hit: 5d8 slashing plus 8d8 force damage.
  • Bite: +18, reach 5 feet. Hit: 7d8 piercing plus 8d8 force damage.
  • Multiattack: Sylric makes 3 attacks: one with his bite and two with his claws.

Sylric 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. Sylric regains spent legendary actions at the start of his turn

Attack (1 action). Sylric makes one attack.                                                                             Teleport (1 action). Sylric teleports up to 120 feet to an unoccupied space he can see. Spell (1-3 actions). Sylric casts one spell from 1st to 3rd level, or he casts a cantrip. It takes a number of legendary actions equal to the level of the spell (cantrips take 1 action). These spells do not take spell slots. He can only use this ability to cast a spell with a casting time of 1 action.

Eldritch Slash (1 action). Ranged Spell Attack, +25 to hit, range 120 feet. Hit: 12d8 damage.                                                                                                                                    Eldritch Armor (3 actions). Sylric gains 40 temporary hit points until the start of his next turn. During this time, any creature who attacks him takes 10 damage.