Avariel, Saint of the Last Door

Legendary Resistance (4/Day). If Avariel fails a saving throw, it can choose to succeed instead.

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

Magic Weapons. Avariel's weapon attacks are magical.

Immutable Purpose. Avariel can't be magically compelled to leave the cathedral or permit a creature to pass through the Last Door. Effects that would magically alter its memories, alignment, loyalties, or purpose automatically fail.

Guardian's Restraint. Avariel doesn't attack a creature merely for entering the cathedral. If a hostile creature puts away its weapons and ceases hostile actions, Avariel doesn't attack that creature unless necessary to prevent it from passing through the Last Door.

Judgment of Violence. When a creature damages Avariel, Avariel can immediately make one Judgment Strike against that creature. A creature can trigger this effect only once per turn. Avariel can use Judgment of Violence no more than three times per round.

Perfect Reprisal. If damage that triggers Judgment of Violence resulted from a critical hit, the resulting Judgment Strike is also a critical hit if it hits.

Phase Two -- In phase two the following ability is added to Acariel's magazine.

Aura of Final Judgment. While Avariel is in his second phase, a hostile creature that starts its turn within 30 feet of Avariel takes 10 radiant damage.

Multiattack. Avariel makes three attacks with the Sword of the Last Door. It can replace one attack with Merciful Judgment.

Sword of the Last Door. Melee Weapon Attack: +15 to hit, reach 10 ft., one target.
Hit: 17 (2d8 + 8) slashing damage plus 13 (3d8) radiant damage.

Average: 30 damage.

Judgment Strike. Melee or Ranged Weapon Attack: +15 to hit, reach 10 ft. or range 120 ft., one creature.  Hit: 17 (2d8 + 8) force plus 13 (3d8) radiant.  Avariel's sword flashes rather than physically traveling when this attack is made at range.  After taking this damage, the target must succeed on a DC 15 Strength saving throw or be pushed 5 feet directly away from Avariel.

Merciful Judgment. One creature Avariel can see within 60 feet must make a DC 22 Constitution saving throw.

On a failure, the creature gains one Judgment Mark. On a success, one Judgment Mark already affecting the creature is removed.

The effects are cumulative:

One Mark: The creature's speed is halved.

Two Marks: The creature is restrained.

Three Marks: The creature is petrified.

A creature petrified this way remains petrified until restored by greater restoration, wish, comparable magic, or Avariel willingly releases it.

A creature that hasn't gained another Judgment Mark for 1 minute loses all its Judgment Marks.

Cast Out (Recharge 5–6). Avariel releases a concussive wave. Each creature of Avariel's choice within 30 feet must make a DC 22 Strength saving throw. On a failure, the creature takes 27 (6d8) force damage, is pushed up to 30 feet directly away from Avariel, and falls prone. On a success, it takes half damage and isn't pushed or knocked prone.

This movement doesn't provoke opportunity attacks.

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

Step Between Moments. Avariel teleports up to 30 feet to an unoccupied space it can see.

Sword Strike. Avariel makes one Sword of the Last Door attack.

Disarm. One creature within 10 feet holding an object must succeed on a DC 22 Strength or Dexterity saving throw (target's choice) or drop one object Avariel chooses. Avariel can cause the object to land anywhere it chooses within 20 feet of the creature.

Enough (Costs 2 Actions). Avariel uses Cast Out if available.

Phase Two — The Last Judgment

Divine Reconstitution (1/Day). When Avariel is reduced to 0 hit points while at least one Petrified Penitent remains in the cathedral, any excess damage is ignored. Avariel falls, and Divine Reconstitution activates.

Its body collapses and its sword falls from its hand. Its wings catch fire and burn away until only the bones remain. Deep, burning fissures rip across its body, glowing from within. Then it settles to the ground and convulses once. Next to it, the sword shatters into a million tiny shards.

At the beginning of Avariel's next turn, every Petrified Penitent turns its head toward the creatures fighting Avariel.

Avariel's fingers move as its hand closes on the broken hilt of the Sword of the Last Door.

The shards of the sword come back together with a sound like glass reforming, flaming streaks of blackness binding the pieces into a whole.

It plants one hand against the floor. The ruined bones of its wings drag behind it as it pushes itself upright. The burning fissures across its body glow like magma beneath stone.

Avariel then rises with 229 hit points. All conditions affecting Avariel end, as do any spells or magical effects imposed on Avariel by another creature.

Its wings are destroyed, it loses its flying speed, and Judgment of Violence can now trigger four times per round.

Avariel says:  “I asked you not to make me do this.”

Communion with the Fallen

While in its second phase, at the beginning of each of its turns Avariel may destroy one Petrified Penitent it can see within 120 feet to choose one of the following effects:

Restoration. Avariel regains 25 hit points.

Renewed Resolve. Avariel regains one expended use of Legendary Resistance.

Renewed Judgment. Cast Out immediately recharges.

Purification. One spell or condition currently affecting Avariel ends.

Once a Petrified Penitent is consumed this way, the statue crumbles into ordinary dust and cannot be used again.

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