Archflame Marie Etross

Arcflare. Some of Archflame Marie Etross' abilities use stacks of Arcflare. Stacks of Arcflare empower her various abilities. When successfully dealing damage to a creature, she gains 1 Arcflare stacks. She starts combat with 0 stacks.

Ascension of the Ember Crown. Marie Etross... [basically ascend into phase 2 of boss fight] (go up to some amount hp, gain stacks of Arcflare, temp hp = to stacks * 2)

Avatar of Desolation. Once Archflame Marie Etross'  Ascension of the ember crown triggers, she gains this trait.

• The Archflame gains one stack of Arcflare at the start of each of her turns.
• All damaging evocation spells that the Archflame uses deal 1 additional damage die per 5 stacks of Arcflare, minimum 1 (round down).
• Firestorm no longer costs stacks of Arcflare.
• The radius of Firestorm increases to 15ft.
• The Archflame gains resistance to Acid, Cold, Lightning, Necrotic, Poison, Radiant, and Thunder damage.

Arcane Siphon. When a creature that she can see casts an evocation spell within 30ft of her, Archflame Marie Etross can drain some of its energy. She gains one stack of Arcflare per level of the spell, minimum 1.

Emblazoned Flame. Archflame Marie Etross' fire damage ignores normal resistance, and causes immunity to be treated as if it was resistance instead.

Arcflare Bolt. Ranged Weapon Attack: +7 to hit, range 90/120 ft., 1 target. Hit: 1d4 + Arcflare stacks fire damage.

Spellcasting. Archflame Marie Etross casts one of the following spells, using Charisma as the spellcasting ability. Additionally, she may spend 2 stacks of Arcflare to increase the level of a spell by 1 when casting it. (spell save DC 15, +7 spell attack bonus):
At Will: Chaos Bolt, Burning Hands, Chromatic Orb
2/Day each: Aganazzar's Scorcher, Hellish Rebuke
1/Day each: Fireball, Melf's Minute Meteors

Firestorm. The Archflame creates a swirling maelstrom of heat in a 10ft sphere around her. Any creature that enters the sphere or ends its turn inside it takes damage equal to the Archflame's stacks of Arcflare. While this ability is active, the Archflame loses one stack of Arcflare at the end of each of her turns. This ability can be dismissed as a bonus action on a future turn.

Flameward (Recharge 5-6, costs 3 stacks of Arcflare). The Archflame protects herself with evocation magic, gaining temporary hp equal to her stacks of Arcflare.

Avatar of Desolation. Archflame Marie Etross can take a total of 3 mythic actions at the end of other creatures turns, choosing from the options below. Only one mythic action can be used at a time. She regains all mythic actions at the start of her turn.

Pyrrhic Execution (Costs 3 Actions and consumes all stacks of Arcflare). The Archflame lets loose a bolt of pure energy towards a target within 90ft. The target must make a DC 15 Dex saving throw, taking half on a success, or take 1d4 damage per stack of Arcflare consumed with this ability.

Flame Pulse (Costs 2 Actions and 2 stacks of Arcflare). The Archflame lets loose a wave of fiery magic. All creatures within 60ft must make a DC 15 Dex saving throw take damage equal to the number of Arcflare stacks she has.

Flameward (Costs 1 Action). The Archflame uses Flameward.