Ala'ris, Slayer of Myth

Magic Resistance. Ala'ris has Advantage on saving throws against spells and other magical effects.

Blessed by Zem'raya. Ala'ris can use up to two reactions.

Blood of the Winter Queen. As the grandchild of the Queen of the Winter court, Ala'ris' blood runs with divine power and authority. Any fey creature of CR 8 or lower obeys him without question, any creature with a fey ancestry is supernaturally compelled to obey him or earn his favor, the form in which this takes shape is determined by the DM.

Legendary Resistance (4/Day). If Ala'ris fails a saving throw, she can choose to succeed instead.

Experience of the Mythic Slayer. Ala'ris is known throughout the multiverse as a slayer of dragons, giants, demons and any creature that threatens the Feywild or displeases his divine grandmother. Whenever hostile creature of size large or bigger within 40ft of Ala'ris makes an Attack action or uses a breath weapon against him for the first time each turn, he can use his Counterattack reaction as a free action.

Mythical Dragonslayer. Ala'ris has advantage against a dragon's breath weapon and any spell cast by it or by a draconic sorcerer.

Mythic Swordsman. Any weapon attack performed by Ala'ris can be considered magical and cleaving, striking every creature 5ft feet in the direction of his choosing on hit and bypassing any resistances. (You roll and hit any creature with an AC lower than the result, ignoring)

Winterblessed Soulstealer. Ala'ris wields the mythic blade Winter's Bite, a magical weapon made out of the Winter Queen's own power with the ability to trap the soul of any creature slayed by it, preventing resurrections or reanimation. A soul trapped this way can only be released if the blade is broken or a creature attuned to it releases the souls voluntarily.

A Demigod's Wings. If Ala'ris falls, he falls 60ft per round and doesn't take fall damage.

Divine Will. (Recharge after Short or Long Rest). If Ala'ris would be reduced to 0 hit points or killed through magical means, his current hit points instead become 150. After this ability activates, Ala'ris becomes surrounded by an Aura of Frost, making each creature of Ala'ris' choice within 30ft of the Archfey to take 10 (3d6) cold damage at the beginning of each of their turns, this damage is considered holy and thus ignores any resistances and immunities and cannot be negated in any way. 

Skybreaker (2/Day). When Ala'ris deals damage to a winged creature or a creature under a spell that grants it flying with a melee attack, he can force the creature to make a strength saving throw (DC 23), or have its flying speed be reduced to 0 until the start of Ala'ris' next turn. If a creature that falls to the ground due to this feature, the falling damage is doubled.

Spellcasting. Ala'ris is a 20-level spellcaster. His spellcasting ability is Charisma (spell save DC 20, +12 to hit with spell attacks). Ala'ris has following Paladin and Sorcerer spells prepared:

Cantrips (at will): Chill Touch, Ray of Frost, Message, Frostbite 

1st level (4 slots): Command, Detect Magic, Divine Smite, 

2nd level (3 slots): Misty Step, Shining Smite, Detect Thoughts

3rd level (3 slots): Dispel Magic, Summon Fae, Sleet Storm

4th level (3 slots): Dimension Door, Dominate Beast, Ice Storm, 

5th level (2 slots): Cone of Cold, Dominate Person, Far Step

Multiattack. Ala'ris makes three Winter's Bite attacks. He can use Spellcasting, Blizzard Slice or Expose the Heart in place of one of those attacks. 

Winter's Bite. Melee Weapon Attack: +17 to hit, reach 5ft up to three targets. Hit: 16 (2d8 + 8) slashing damage damage plus 16 (4d8) cold damage plus 5 (1d10) radiant or necrotic damage. 

Blizzard Slice (7/Day). Ala'ris dashes forward in a line 5ft wide and as long as his remaining flying movement making a single Winter's Bite attack against each creature caught within the range and leaving behind an obscuring haze of frost.

Expose the Heart (4/Day). Ala'ris strikes at an enemy's weak spot, shattering its balance/ scales / or defenses and revealing its weak spot to him. Ala'ris may choose this weak spot as his target during his next attack. The enemy has three-quarters cover against attack made against this spot, but any hit made to it are critical. 

Titanslayer (Recharge 5-6). Ala'ris channels his magic through his sword before slashing through the air and unleashing a devastating wave of frost and divine power. Dexterity Saving Throw: DC 23, each creature in a 60ft Cone. Failure 22 (5d8) slashing damage plus 22 (4d10) cold damage and movement halved and suffer the bleeding condition (Lose 2d8 hit points at the beginning of each turn until healed). Success. Half damage and movement halved. Damage done this way is considered holy and thus ignores any resistances and immunities and cannot be negated in any way.   

Warrior's Blessing (3/Day). Ala'ris chooses a worthy ally and bestows his blessing on them, granting them advantage on all attack and saving throws until the beginning of Ala'ris' next turn.

Parry. Ala'ris adds 5 to his AC against a weapon attack that would have hit him. To do this he has to know that the attack is coming and has to be wielding a weapon.

Counterattack. After a creature performs an attack action against Ala'ris he can attack the target with Winter's Bite. If the target is a creature of size large or bigger and is more than 5ft away, a Winter's Bite attack performed this way instead slashed through the air and becomes a ranged weapon attack.

Winter's Mist. Ala'ris casts the Misty Step spell without expending a spell slot in reaction to a create dealing damage to him. This can be used before any saving throws have to performed by him as a consequence of the damage.

Sparkstealer (Recharge 4-6). When Ala'ris rolls a saving throw against a dragon's breath weapon or an area of effect spell that deals damage (such as Fireball or Cone of Cold) he can reduce the number of damage dice rolled by 8 and his weapon becomes charged with that energy. On his next attack he can expend up to half the number of dice reduced this way and add the damage that would have been dealt this way in addition to any other damage he would deal. 

Ala'ris can use up to three legendary actions. Only one legendary action can be taken and at the end of each creature's turn. He regains all legendary actions at the beginning of his turn.

Swift as a star. Ala'ris moves up to 25ft in any direction. Provoking attacks of opportunity only if he chooses.

Attack. Ala'ris makes one attack with his Winter's Bite attack.

Freezing Gale (Cost 2 Actions). Ala'ris casts the Cone of Cold spell without expending a spell slot.

Glory beyond mortality. If Ala'ris has less than half his hit points or he is a battle worthy of myth (as deemed by the DM) he gains access to his mythic actions. These actions can be used instead of a legendary action, counting to the legendary action total or during his turn.

Blood of the Divine. Ala'ris regains 4d8 hit points and ends all conditions on himself. This ability can be used even if he is stunned or paralyzed. 

Doombringer of Legend. Ala'ris has advantage on all attacks against a creature of his choice until the end of his turn. if he has made no attacks this turn, he can make up to two Winter's Bite attacks.