The night lords are beings of immense power that rule from the shadows of night.  As mortals rule over the day, their undeath rules the night.  Dracula, Strahd, Vecna, and others are examples of this primeval class of beings.

Expanded Spell List

The Fiend lets you choose from an expanded list of spells when you learn a warlock spell. The following spells are added to the warlock spell list for you.

Fiend Expanded Spells

Spell Level	Spells
1st	Command, Inflict Wounds
2nd	Scorching Ray, Spiritual Weapon
3rd	Glyph of Warding, Spirit Guardians
4th	Dominate Beast, Wall of Fire
5th	Dominate Person, Planar Binding

Crimson Feast

Starting at 1st level, when you reduce a hostile creature to 0 hit points, you gain temporary hit points equal to your Charisma modifier + your warlock level (minimum of 1). 

Dark Metamorphosis

Starting at level 1,  you age at a slower rate. For every 10 years that pass, your body ages only 1 year, and you are immune to being magically aged.

Additionally, at level 6, you can hold your breath indefinitely, and you don’t require sleep, although you still require rest to reduce exhaustion or benefit from finishing short and long rests.

Blood Magic

At level 6, You may cast spells by expending hit dice. One hit dice is consumed per level of the spell cast to a maximum of nine. You take damage equal to the amount rolled on the hit dice. You may not expend more hit dice than you have available when using this feature.

Unholy Power

Starting at level 10, when you cast a cantrip, you may make one weapon attack with your bonus action. 

Sanguine Fury

At 14th  level, you gain inhuman speed in combat. When you take the Attack action or cast a cantrip, you can travel up to 15 feet before each attack to an unoccupied space you can see.

If you attack at least two different creatures with the action, you can make one additional attack with it against a third creature.  Moving using this feature does not provoke attacks of opportunity.