King in Yellow Patron

You serve Hastur, an elder god beyond your comprehension. Across the void he rules in the great city of Carcosa by the mist-covered lake Hali. You have been pulled into this being's service, Likely at the cost of your sanity, probably due to contact with the maddening text know as "The King in Yellow". The king has an affinity for artists, especially musicians, painters and playwrights and will often influence their work after making a pact with them to spread his madness even further.

Expanded Spell list

Beginning at first level, the king in yellow lets you choose from an expanded list of spells, the following spells are added to the warlock spell list for you.

Spell Level	Spells
1st	Dissonant Whisper's, Phantom Mask
2nd	Phantasmal Force, Crown of Madness
3rd	Enemies Abound, Phantasmal Mirror
4th	Hasturs Phantasmal Killer, Summon Aberration (Starspawn only)
5th	Geas, Phantasmal Delirium

Eldritch Phantasm

At 1st level, You may cast the Eldritch Secret granted by your patron as an action, which allows you to paint a vivid picture amongst the battlefield. When you cast this secret, you may conjure a number of illusionary terrain or hazards that fits in a 5ft cube for each eldritch spark you create upon casting. These Phantasmal illusions have the following mechanics:
- You may have up to (your level * 5) ft squares worth of these illusions on the battle field at any given time.
- Creatures who can be effected by illusions treat the phantasms as if they were real danger, and will often avoid them,
- Upon coming into contact with a phantasm a creature must make a wisdom save against your spell save to see through the illusion.
- On a failed save the target takes 1d6 psychic damage and you may apply one of your eldritch invocations that effects damage dealing cantrips to the target.
- On a successful save, the creature takes no damage and the terrain is dispelled.
- You may connect 5ft cubes together, doing so "combines" them allowing the illusion to appear larger or effect more terrain
- When a creature fails a save against combined squares, it takes damage as if it were that many squares (3 5ft square in one illusion, 3d6 psychic) However all combined squares disappear if the creature makes its save

Casilda's Song

Beginning at 1st level, you can utter a few lines from the King in Yellow, weakening the mind of those who hear you. As an action you may force all creatures within 30ft to make a Wisdom saving throw against your spell save DC. On a failure a creature gains vulnerability to psychic damage and disadvantage on their next Intelligence or Wisdom check. You may continue your recitation on your next turn to inflict 1d4 + pb + cha psychic damage to all creatures within 30ft. You may not move whilst reciting and reciting requires concentration. You may recite for a number of turns equal to your proficiency bonus per long rest.

You Sir, should unmask

Beginning at 6th level, The power of the King in Yellow grants you the ability to lay bare the fears of others and use them to your advantage. Whenever you cast an Illusion spell, you may add your charisma modifier to its damage, or add double your charisma modifier if the target is Shaken, Frightened or Demented.

The mists of Lake Hali

At 10th Level, you are surrounded by the chill mists which cover Lake Hali which protect you from harm and reflect your enemies fears. You gain plus 1 AC against any ranged attacks targeting you. As a reaction you may force a creature which moves within 10ft of you to make a wisdom saving throw against you spell save dc. On failure they suffer from the shakened condition until the end of their next turn.

The Yellow Sign

At 14th Level, Your service to the king in yellow has not gone unnoticed and you have been granted the power to invoke the Yellow Sign. Once per long rest you may present the Yellow Sign as an action. All beings within 30ft must make a wisdom saving throw against your spell save dc or suffer from the Demented condition