The Lich

Most Liches don't accept pacts, as they believe their power will eventually subvert all in their path, but some have a more insidious intelligence in which these warlocks become tools of their will, controlling deathly energies and commanding undead minions. While most liches detest the living, these formidable warlocks they choose often come from races that are still yet alive, so that the lich might utilize their ability to infiltrate and affect society in their stead. By the time they become truly suffused with deathly magics, these warlocks often get folded into the inner cult of the lich itself, accepted as protectors of the lich's lair and perhaps even granted some knowledge of the whereabouts of that mighty undead's phylactery. From the moment these warlocks accept their pact, they begin to understand deathly energy in amazing new ways, and as they grow, their very arcane power can replace the needs for corpses and bone piles to assist them in casting their magic spells. Advancing the goals of their patrons further means these unique spellcasters gain affinity with deadly necrotic damage spells, and at their most potent, these Warlocks command all manner of undead, and wreak havoc upon the living with terrible necromantic spells.

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	False Life, Ray of Sickness
2nd	Blindness/Deafness, Wither and Bloom
3rd	Bestow Curse, Summon Undead
4th	Phantasmal Killer, [Tooltip Not Found]
5th	Contagion, Raise Dead

Undead Command

At 1st level, you learn a certain understanding of death itself, you learn to conjure an undead companion which ultimately obeys your will, and you can empower undead with your arcane necrotic energy. You learn the Spare the Dying cantrip, and you learn and can cast Find Familiar once without expending a spell slot before you must finish a long rest to cast it this way again. Whenever you summon a creature with this spell, it gains the undead type and you choose whether it is a bone undead more akin to an animated skeleton or a corpse undead more akin to a zombie.

At 3rd level, when you cast the Summon Beast spell, you can add the undead type to that creature's types, choosing whether it is a bone undead or a corpse undead. 

Additionally, whenever an undead creature you control deals damage to another non-undead creature, that damage counts as magic for the purposes of damage reduction, and you may use your reaction to add 1d6 bonus necrotic damage to that damage. This bonus damage improves to 2d6 at 6th level, and to 3d6 at 14th level.

Forsaken Sacrifice

At 6th level, you learn the fundamental techniques of conjuring undead servants in any situation you might need. You learn the Animate Dead spell and you can cast it once without expending a spell slot before you must finish a short or long rest to cast it this way again. When you cast this spell, you may cause your undead familiar or a beast you summon with the Summon Beast spell to become the basis for your undead creature summoned by the spell. If your familiar or the beast is a bone undead, the spell consumes the familiar to create a skeleton, and if your familiar or the beast is a corpse undead, the spell consumes the familiar to create a zombie. You may end your concentration of the Summon Beast spell in the same turn you cast the Animate Dead spell and receive these benefits. When the spell ends, the transformed corpses turn to harmless dust.

Lastly, the bonus damage from your Undead Command feature improves to 2d6.

Host of Blights

At 10th level in this class, you learn to conduct powerful surges of necrotic power to assault the living and assist the undead. You learn the Blight spell and you can cast it once without expending a spell slot before you must finish a short or long rest to cast it this way again. When you cast this spell, you may add the bonus damage from your Undead Command feature. 

Lastly, you are now well-versed in the means to identify and understand necromantic magic in the utmost. You have advantage on all Intelligence (Arcana) checks regarding Necromancy magic.

Phylactery Agent