Host of Fear

You have accepeted, or have been forced into servitude, by Kal'Shee, the Dark Harvester, allegorie of fear. A host to his Crimson Light, he seeks to preserve your body so that he may survive, and strike fear into others so that he may satiate his unquenchable desires. 

Infernal Reaping

Kal'Shee takes great pleasure in striking fear into the hearts of his enemies, while ensuring that his host survives. Once per short or long rest, you can use your action to channel Kal'Shee, projecting vivid memories and fears into the minds of all creatures in a 15ft sphere centered on you, frightening them for one round. In addition, if you frighten at least one creature, Kal'Shee harvests their souls, bolstering his grasp in this realm, granting you temporary hit points equal to your charisma modifier (minimum of one). The temporary hit points do not stack.

Thirst for Fear

Kal'Shee thirsts for others to fear him, and allows you to strike fear into your enemies souls, while bolstering your resolve. You cannot be frightened by any means, and can do an intimidation check as an action on a creature within 10ft of you. On a success, they are frightened, and you gain temporary hit points equal to your charima modifier. These hit points stack on other effects, such as Infernal Reaping, but can not stack upon themselves.

Unseen Nightmare

Surprise is an excellent tool for creating fear, and things which are unseen can make even the bravest warrior tremble. If you surprise an enemy on the first round of combat, they are frightened of you for the first round. In addition, if you hit a melee attack within the first round of combat, you can become invisible for up to 1 minute. The invisibilty breaks when you attack or cast a spell. When you emerge from invisibility, you frighten the closest enemy within 5ft of you.

Plane of Terror

Once per long rest, you can become terror manifest. You can chose one creature, within 40ft of you, and transport it and yourself to a demi-plane, where it's fears and regrets are projected. Inside, it becomes frightened, and cannot leave by any means, until the effect ends, in up to 10 minutes. The demi-plane is a 120ft cube. When the plane is dispelled, the creature takes 2d10 psychic damage, and is incapacitated for 1 round as it recovers from the harrowing experience. The plane is dispelled early if you fall unconscious. Inside, you and the creature can both operate as normal. Any damage taken or condition suffered inside the demi-plane is still kept in the original plane. If the target's fear involves a creature, a place, or a person, illusory copies are summoned. They act, and feel normal, but can not harm the target.