Alkalyne, the Venomous

Epic Boss Hit Points. Increase the striga's starting hit points and hit dice by 57 (6d10 + 24) for each player character above four, or reduce its starting hit points and hit dice by that amount for each player character below four.

Exotic Poisoner. Whenever a creature casts a spell or uses a trait or feature that would cure or remove one of your poisons (such as casting lesser restoration), the creature must first make an ability check using its spellcasting ability DC 18 (or its Charisma modifier, if the spell or special ability does not specify a spellcasting ability score). On a failed check, the creature’s spell, trait, or feature fails and has no effect. Any material components used are expended, and any spell slot expended is wasted.

Master Poisoner. His poisons bypasses resistance and turns immunity into resistance. 

Necrotic Aura. A creature that starts its turn within 30 feet of the Striga takes 10 (3d6) Necrotic damage.

Regeneration. The striga regains 10 Hit Points at the start of its turn if it has at least 1 Hit Point and isn't in sunlight or running water. If the striga takes Radiant damage or damage from holy water, this trait doesn't function at the start of the vampire's next turn.

Alkalyne always takes its turn on Initiative count 20. On its turn, the Alkalyne can use its movement and interaction as normal. However, it does not take an action or Bonus Action on its turn unless forced to do so by a spell or other effect. Instead, the Alkalyne takes one of the following Epic Actions at the end of each player character's turn:

Neurotoxin(1/Round). Melee Attack Roll: +10, reach 10 ft. Hit: 24 (4d6 + 6) Necrotic damage. The target's Hit Point Maximum is reduced by an amount equal to the Necrotic damage taken, The creature has to make a DC 18 Constitution saving throw or become Dazed for 1 minute  (save ends at end of turn). You can move or take an action on your turn, not both. You can’t take Bonus Actions.

Venipuncture. Melee Attack Roll: +10, reach 5 ft. Hit: 11 (1d8 + 6) Piercing damage and 15 (4d6) Poison damage.

Knockout Gas (1/round) Unleashes a 15-ft. radius poisonous mist centered on a point within 60 ft. DC 18 Constitution save or take 16 (4d6) Poison damage and incapacitated until the end of their next turn. Half damage on success.

Violet Hallucinogen (1/round)  Melee Attack Roll: +10, reach 5 ft. Hit: 11 (1d8 + 6) Piercing damage and needs to maks a DC 18 Wisdom saving throw or they choose targets randomly for 1 minute. Save at end of each turn.

Tranquilizing Toxin. One target you choose within range must make a DC 18 Constitution saving throw or take 32 (8d6) Poison damage and become poisoned until the end of their next turn. While poisoned in this way, the target is also stunned. On a successful saving throw, the target takes half damage and is not poisoned.

Warping Step. Alkalyne teleports up to 40 feet in a straight line, moving through the spaces of other creatures. Each creature whose space Alkalyne passes through is subjected to the following effect. Dexterity Saving Throw: DC 18. Failure: The target is pushed 10 feet away from the striga and has the Prone condition.

Epic Resistance. The striga chooses one condition, spell, or other effect currently affecting them and rolls 1d20. On an 11+, the effect ends on it. The striga can use this action even if it would otherwise be unable to take actions, its actions are being controlled by another creature, or if a spell or effect alters its game statistics.

Elusive Shift: Trigger. When a creature hits Alkalyne he can teleport 30 feet away to an unoccupied location.