You have made a pact with a cryptic and secretive entity with goals unknown to even you, maybe even having no goals. The being's aims either never were known or were lost to the sands of time. They may have forgotten their own goals as well, making a deal with you to recover their memory or past selves. Others see beings such as these to be insane or dangerously secretive.

The Cryptic 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.

Cryptic entities like this include The Raven Queen, Edrun Of Far Places, Ignotus, and Jergal, The Lord of the End of Everything.

Sentinel Creature Starting at 1st level, you gain the service of a spirit sent by your Patron to watch over you. The spirit assumes the form and game statistics of a tiny beast, probably a creature associated with your patron, if there is one. It always obeys your commands, which you can give telepathically while it is within 100 feet of you. While the creature is perched on your shoulder, you gain darkvision with a range of 30 feet

A bonus to your passive Wisdom (Perception) score and to Wisdom (Perception) checks. The bonus is your Charisma modifier.

While perched on your shoulder, the creature can’t be targeted by any attack or other harmful effect and only you can cast spells on it. You can see through the creature's eyes and hear what it hears while it is within 100 feet of you.

In combat, you roll initiative for the creature and control how it acts. If it is slain, you gain advantage on all rolls against the killer for the next 24 hours.

The creature doesn't require sleep.

While it is within 100 feet of you, it can awaken you from sleep as a bonus action.

The creature vanishes when it dies, if you die, or if the two of you are separated by more than 5 miles.

At the end of a short or long rest, you can call the creature back to you no matter where it is or whether it died and it reappears within 5 feet of you.

Soul of the Sentinel At 6th level, you gain the ability to merge with your sentinel spirit. As a bonus action when your creature is perched on your shoulder, your body merges with your creature's form. While merged, you become Tiny, you replace your stats with the creature’s, and you can use your action only to Dash, Disengage, Dodge, Help, Hide, or Search. During this time, you gain the benefits of your creature being perched on your shoulder. As an action, you and the creature return to normal.

Spirit Shield At 10th level, your Patron grants you a mysterious knowledge of life and death. You gain advantage on death saving throws, immunity to the frightened condition, and resistance to necrotic damage.