Special Equipment. Xeletha wields the weapons Shattered Sun and Holy Collider.

Amaurotic Radiance. Xeletha regains 30 hit points at the start of her turn as long as she has at least 1 hit point, restoring any lost or severed member. Xeletha dies only if she starts her turn with 0 hit points and doesn't regenerate.

Anathematic Secrecy. Xeletha can't be targeted by any divination magic or perceived through magical scrying sensors. She also doesn’t require air or sleep.

Fey Ancestry. Xeletha has advantage on saving throws she makes to avoid or end a condition on herself, and magic can't put her to sleep.

Black Flash. When Xeletha scores a critical hit, roll a percentile die. On a roll of 80 or higher, the critical hit deals maximum damage, and until the end of her next turn, her next attack roll has its critical range increased by 1. If her next attack roll is another critical hit, the same effect occurs but with critical range increased by 2, and the effect persists until he fails scoring a critical hit. By failing to score a critical hit thus breaking the streak, Xeletha can't activate Black Flash again until she finishes a short or long rest.

Benevolent Script (5/day). If Xeletha fails a saving throw, she can choose to succeed instead.

Flames of Xaros. Xeletha deals double damage to non-player characters that aren’t titans of deities (bypassing their resistances, immunities, and absorption). If Advenia kills a creature, she instantly destroys their body, mind, consciousness, subconsciousness, and soul (bypassing any effect that would prevent this from occuring).

Additionally, any nonmagical weapon that hits Xeletha burns. After dealing damage, the weapon takes a permanent and cumulative −1 penalty to damage rolls. If its penalty drops to −5, the weapon is destroyed.

Nonmagical ammunition that hits Xeletha is destroyed after dealing damage.

Immense Strength. Xeletha counts as two sizes larger when determining her carrying capacity and the weight she can push, drag, or lift. Xeletha's long jump and high jump is up to 120 ft., with or without a running start.

Magical Knowledge. Once per round, if Xeletha perceives the casting of a spell, the spell's effect, or both, she can make an Intelligence (Arcana) check to identify the spell. The DC equals 15 + the spell’s level.

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

Xaric Weapons. Xeletha's weapon attacks are magical. When she hits with any weapon, the weapon deals an extra 18 (4d8) fire damage plus 18 (4d8) radiant damage (included in the weapon attacks below).

Strongest in History (Recharges after a Short or Long Rest). If Xeletha would be reduced to 0 hit points, her current hit point total instead resets to 756 hit points, she recharges her Xaric Ignition: Cataract of Fire, and she regains 3 expended uses of Benevolent Script. Additionally, Xeletha can now use the options in the "Mythic Actions" section for 1 hour. Award a party an additional 155,000 XP (310,000 XP total) for defeating Xeletha after her Strongest in History activates.

Unyielding Essence. Xeletha is immune to any spells or effects that would alter her form, as well as those that would read her thoughts, determine if she is lying, or magically influence her thoughts or behavior.

Multiattack. Xeletha makes three Unarmed Strike, Xaric Ignition, or Xaric Fūga attacks, or any combination of the three. She may replace one of the attacks with a Shattered Sun or Holy Collider attack.

Unarmed Strike. Melee Weapon Attack: +19 to hit, reach 5 ft., one target. Hit: 19 (2d8 + 10) bludgeoning damage plus 18 (4d8) fire damage plus 18 (4d8) radiant damage.

Xaric Ignition. Ranged Spell Attack: +18 to hit, range 120 ft., one target. Hit: 25 (3d10 + 9) fire damage. Objects and structures takes double damage that can't be prevented or reduced in any way.

Xaric Fūga. Ranged Spell Attack: +18 to hit, range 120 ft., one target. Hit: 31 (5d8 + 9) fire damage.

Shattered Sun. Melee or Ranged Weapon Attack: +22 to hit, reach 5 or range 20/60 ft., one target. Hit: 16 (1d6 + 13) piercing damage, or 17 (1d8 + 13) piercing damage if used with two hands to make a melee attack, plus 18 (4d8) fire damage plus 18 (4d8) radiant damage. If Xeletha scores a critical hit with it, the target takes extra radiant damage equal to half its hit point maximum.

Holy Collider. Melee Weapon Attack: +22 to hit, reach 5 ft., one target. Hit: 17 (1d8 + 13) bludgeoning or slashing damage (Xeletha's choice), plus 4 (1d8) fire damage plus 18 (4d8) fire damage plus 18 (4d8) radiant damage.

Xaric Immolation (Recharge 5-6). Melee Spell Attack: +18 to hit, reach 10 ft., one target. Hit: 39 (6d12) fire damage plus 39 (6d12) radiant damage. This damage can't be reduced or prevented in any way. This damage can't be reduced or prevented in any way. If the target is a creature, it must succeed on a DC 26 Constitution saving throw or lose 16 (3d10) hit points at the start of each of its turns due to being immolated by xaric flames. Each time Xeletha hits the immolated target with this attack, the damage dealt by the immolation increases by 16 (3d10). Any creature can take an action to put out the xaric flames with a successful DC 18 Wisdom (Medicine) check. The wound also closes if the target receives magical healing.

Xaric Ignition: Cataract of Fire (Recharges after 1 minute). Xeletha enhances the Flames of Xaros that she wields by amplifying their area and their power to a catastrophic level. Xeletha chooses a 100-foot cone, a 200-foot sphere centered on her, or a 300-foot line that is 30 feet wide. Each creature of her choice in that area must make a DC 26 Constitution saving throw, losing 100 hit points on a failed save, or half as much on a successful one. A creature that has 50 hit points or fewer bursts into Xaric Flames, disintegrates, and dies. This effect bypasses any barrier, including creations of magical force, such as the wall created by the wall of force spell.

Empyreal Barricade (Recharge 5-6). Xeletha erects a sun-shaped barrier of the Flames of Xaros that neutralizes the effects of guaranteed hits targeting her (Except Critical Hits). If the attack was originally a hit but became guaranteed due to a Domain Expansion, it reverts to requiring an attack roll. This barrier lasts for 1 minute, requires concentration, and Xeletha must keep her hands together performing the release seal for the entire duration, or the barrier dissipates.

Gammaflare Technique (Recharge 5-6). Xeletha cloaks herself in the Flames of Xaros for 1 minute and she must concentrate on it (as if concentrating on a spell). For the duration, Xeletha can't be subjected by an effect that automatically deals damage (Except Critical Hits). If the effect originally had an attack roll and turned into an effect that automatically deals damage due to a Domain Expansion, this effect needs an attack roll as normal.

Moreover, Xeletha ignores spells and magical effects that she touches, but she can't use any spell, magical effect, and her magical item attunements are suppressed for the duration.

Positive Energy Transfer. Xeletha touches another creature. The target magically regains hit points equal to Xeletha's Amaurotic Radiance heal. When Xeletha uses this action, her Amaurotic Radiance trait stops functioning until the end of her next turn.

Xaric Incineration. When Xeletha is subjected to an attack or effect with automatic hit or guaranteed damage, such as the magic missile spell, she takes no damage instead.

Celestial Cauterization. Xeletha makes one Unarmed Strike or Xaric Ignition attack.

Overwhelming Presence (Costs 2 Actions). Each creature of Xeletha's choice that is within 120 feet of her and aware of her must succeed on a DC 21 Wisdom saving throw or become charmed or frightened (Xeletha's choice) until the end of its next turn.

If Xeletha's Strongest in History trait has activated in the last hour, she can use the options below as legendary actions.

Telluric Strike (Costs 2 Actions). Xeletha makes one Unarmed Strike attack. On a hit, the target must succeed on a DC 27 Constitution saving throw or pushed 30 feet away from her, falling prone.

Canvas of Creation (Costs 3 Actions). A spatial distortion extends out from Xeletha in a 650-foot radius and stays in place. The area becomes a consecrated ground resembling a second sun.

The area lasts for 1 minute so long as Xeletha maintains concentration (as if concentrating on a spell) - or until Xeletha loses concentration. Within this area, her Xaric Immolation attack has its range increased to 60 ft. and automatically hits, and her Xaric Ignition attack hits all creatures within range on a single attack roll.

Whenever this effect ends, whether it reached its full duration or Xeletha loses concentration, she receives 1 level of exhaustion.