1: Dark Blessing, Diabolical Curse
6: Dogs of Below
10: Blasphemous Act
14: Hurl through Hell
When you reduce a creature to 0 hit points, or when a creature under a spell effect you control is reduced to 0 hit points, you gain a number of temporary hit points equal to your spellcasting ability modifier + your warlock level (minimum 1).
You can use a bonus action to place a curse on a creature you can see within 30 feet. The curse lasts for 1 minute, and ends early if the target dies, you die, or you become incapacitated. The curse has the following effects:
Choose fire damage or necrotic damage. When you deal damage against the cursed creature, it takes an additional 1d4 damage of the chosen type. This bonus increases by 1d4 at 10th level, and again at 15th and 20th level.
Your patron siphons the cursed creature’s life force and pays you a dividend. When the cursed creature dies, you regain hit points equal to your spellcasting ability modifier + your warlock level (minimum 1).
Once you have used this feature, you can’t use it again until you finish a short or long rest
Starting at 6th level, when you kill a creature targeted by your Diabolical Curse or under the effects of one of your warlock spells, you can bid your patron conjure into your service either a death dog or a ghoul (your choice) into an unoccupied space within 30 feet. The creature rolls its own initiative, has its own turns, and obeys your verbal commands. The creature disappears after 1 minute, when you are knocked unconscious, or when it is reduced to 0 hit points.
At 15th level, you can have your patron conjure for you either a hell hound or a wight instead.
Once you have used this feature, you can’t use it again until you finish a short or long rest.
At 10th level, you can siphon away divine power intended for the gods’ chosen. At the end of each long rest, you gain a Channel Divinity feature. This feature must be from a cleric archetype and granted to clerics of 2nd level. Alternatively, you can instead gain Turn Undead with the benefit of the Command the Turned empowerment.
Once you have used the chosen cleric feature, you can’t use it again until you finish a short or long rest.
At 14th level, you can condemn a creature to see the abyss in all its unknown and soul-consuming glory. When you hit a creature with an attack, you can use this feature to instantly fling it through the most horrific vistas of the multiverse. The creature disappears until the end of your next turn, reappearing in the space it previously occupied, or the nearest unoccupied space. If the creature is not a fiend, it takes 10d10 psychic, fire, or cold damage (your choice).
Once you have used this feature, you can’t do so again until you finish a long rest.