Blade Infusion

Prerequisite: Pact of the Blade feature

Your pact weapon deals an extra 1d6 damage of a type that matches your patron, at the DM's discretion.

Call of the Summoner

Prerequisite: Pact of the Chain feature

Whenever you cast a spell that summons one or more creatures to your service, you don't need concentration to maintain control of the spell. You can't cast such spells again until the last one ends, and you can end the spell at any time (no action required).

Control Magic

Prerequisite: Dancing lights, druidcraft, mage hand, prestidigitation or thaumaturgy cantrips

These, and other similar cantrips with your DM's discretion, don't require spell components and actions to cast or control.

Dark Knowledge

Prerequisite: Pact of the Tome feature

Whenever you roll for Arcana, History, Nature, Religion or Medicine and you are proficient with the skill, roll it with Charisma instead of Intelligence or Wisdom. In addition, you gain proficiency in one of those skills of your choice.

Deadly Toxins

Prerequisite: any cantrip that deals acid or poison damage

Creatures that get hit or fail to resist your acid or poison damage dealing cantrips are poisoned, and take 1d6 poison or acid damage at the start of their turns, the same damage type that the cantrip dealt. At the start of each of their turn, after taking damage, they make a Constitution saving throw against your spell save DC to stop the effects.

This damage increases to 1d8 at 5th level, 1d10 at 11th level and 1d12 at 17th level.

Essence Manipulation

Prerequisite: any cantrip that deals necrotic damage

Whenever you deal damage with one of these cantrips, you can give a creature within 30 feet of you a number of temporary hit points equal to half of the damage dealt with the cantrip. The temporary hit points last for 1 minute.

Freezing Death

Prerequisite: any cantrip that deals cold damage

Creatures that fail to resist your cold damage dealing cantrips have their speeds halved, and can't take reactions and bonus actions until the start of your next turn.

If the cantrip doesn't require a saving throw to resist its effects, the creatures make a Constitution saving throw, suffering those same effects on a failed save.

Hex of Misfortune

You can use your patron's power to disrupt a creature. With an action, a creature within 60 ft. of you must make a Wisdom saving throw against your spell save DC. On a fail, until the start of your next turn, that creature has disadvantage on its ability checks, attack rolls and attackers have advantage on their attack rolls against it.

High Voltage

Prerequisite: any cantrip that deals lightning damage

After casting a spell with an action on your turn, you can cast a cantrip that deals lightning damage with a bonus action.

When you reach 5th level, you can cast two cantrips that deal lightning damage with an action on your turn.

Power over Power

Prerequisite: counterspell or dispel magic spells

Whenever you cast counterpell or dispel magic and is required to make an ability check, you can add your proficiency bonus to that ability check.

You can also cast those spells in place of the ones you can cast with your mystic arcanum feature, as spells of the same level of the spell you are casting in its place.

Radiance

Prerequisite: any cantrip that deals radiant damage

Creatures that get hit or fail to resist your radiant damage dealing cantrips emit bright light in a 15-foot-radius around them until the start of your next turn. While it lasts, they can't benefit from invisibility, can't take the Hide action, and attackers can't have disadvantage on attack rolls against them.

Surging Flames

Prerequisite: any cantrip that deals fire damage

Creatures that get hit or fail to resist your fire damage dealing cantrips take an additional 1d6 fire damage. Every creature adjacent to them must make a Dexterity saving throw against your spell save DC, taking half as much damage as the first creature on a failed save.

This damage increases to 1d8 at 5th level, 1d10 at 11th level, and to 1d12 at 17th level.

Tendrils of Agony

Prerequisite: 5th level

You can cast magic tentacles, limbs or strands depending on your patron to grab and entangle a creature. With an action, you are able to affect a single creature within 60 ft. that you can see with the Evard's black tentacles spell, except that the damage type can change to match your patron, at your DM's discretion.

Once you use this feature, you can't use it again until you finish a short or long rest.