Ushanti Remnant

Nimble: This creature can disengage as a bonus action.

Melee Weapon Attack: +10 to hit, reach 15 ft, 1 target. Hit: 12 (2d12 + 4) slashing damage. 

Special Melee Attack: Can be done only while invisible, with advantage. Attack: +10 to hit, range 5 ft., 1 target. Hit: 20(3d12 + 4) [necrotic damage] target must make a DC 15 constitution saving throw or be paralyzed. The target can make a save at the end of each turn.

Disengage

Attack of Opportunity 

Leap of the Ascended: (Costs 2 Actions): The creature leaps with supernatural speed, sending loose material aloft, reaching up to 60ft high, then plunges down with its blade drawn pointed directly down. It slams into the ground, fracturing the terrain in a 20ft radius, making it difficult terrain. Any creature caught in the impact radius suffers 3d12 force damage and must make a DC 15 dexterity saving throw, falling prone on a failure or receiving half damage on a success.

Spectral Warrior (Cost 1 Actions). As a bonus action, this creature can become invisible for the rest of its turn. 

Legendary Resistances (Costs 1 Action): If this creature fails a save, it can use a legendary action to succeed instead.