Undyne The Undying

Intimidating: Undyne has advantage on Intimidation checks.

Undying Blood: Undyne has advantage on Constitution saving throws/checks.

Strongest Monster: Undyne has Advantage on Strength saving throws/checks.

Death Defying: If a hit from an attack reduces Undyne's hit points to zero, roll a d20. If the roll is 1-9, then she dies. If it is 10-20, she gains 10d10 hit points back.

Multiattack: Undyne makes four Spear of Justice attacks and one soul change.

Spear of Justice: Melee Weapon Attack: +9 to hit, reach 5 ft., 1 target. Hit: 8 (1d8 + 8) piercing damage plus 8 (2d8) force damage.

Soul Change: Undyne swipes her spear and a magical beam shoots forth. The target then either becomes petrified unable to move from Undyne, or vice versa. When petrified, they may not be able to move from their spot and can only engage with Undyne.

Magic Spears: Undyne summons up to 25 magical spears and shoots them at whoever she targets. Each spear does 1d4 force damage and has a +9 to hit.

Spear Circle (Recharge 5-6): Undyne summons a circle of spears 10 ft. around a single target. The spears then proceed to close around the target. The target must make a Dexterity saving throw (DC 18), or take 22 piercing damage (3d10) and 22 force damage (3d10) on a failure, or half as much on a success.

Undyne can take 3 Legendary Actions, but only after another creatures turn. She gains all Legendary Actions at the beginning of her turn.

Magic Spear: Undyne Shoots 5 magic spears at whoever she targets. Each spear does 1d4 force damage and has a +9 to hit.

Spear Circle (2 Actions): Undyne uses Spear Circle.