Innate Spellcasting. The warlock’s innate spellcasting ability is Charisma. It can innately cast the following spells (spell save DC 15), requiring no material components:

At will: detect magic, speak with dead

Form of Dread (3/day). the warlock gains the following features for the next 1 minute;

• 1d10+8 temp hitpoints
• when you hit a creature they must make a DC 15 wis save or become frightened until the end of the creature next turn

Undying Constitution. the warlock doesn't need to eat, breathe, or drink 

Multiattack. The Warlock makes either two eldritch blast attacks or it use's its dagger and makes a vampiric drain.

Dagger. Melee or Ranged Weapon Attack: +5 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 4 (1d4 + 2) piercing damage. on a hit a creature takes an extra 4 (1d8) necrotic damage.

Vampiric Drain. Melee Spell Attack.+7 to hit, reach 5 ft., one target. Hit: 14 (4d6) necrotic damage and on a hit the warlock regains half of the damage dealt with its vampiric drain ability. once per turn on a hit a creature takes an extra 4 (1d8) necrotic damage.

Eldrtich Blast. Ranged Spell Attack: +7 to hit, range 300 ft., one target. Hit: 10 (1d10+4) force damage., once per turn on a hit a creature takes an extra 4 (1d8) necrotic damage.

Spellcasting. The warlock is a 8th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 15, +7 to hit with spell attacks). It regains its expended spell slots when it finishes a short or long rest. It knows the following warlock spells:

Cantrips (at will): mage hand, minor illusion, prestidigitation

1st–4th level (2 4th-level slots): arms of Hadar, bane, false life, phantasmal force, death ward, dimension door, greater invisibility, blight, vampiric touch, phantom steed