Dramatis Personae: Great Old One Patrons includes:
17 Variant Great Old One class features! Customize your warlock of the Great Old One to represent a specific entity such as The Worm that Walks or The Leviathan. Each strange entity is different, and so are they warlocks!
Each Great Old One patron includes an additional feature, to update the original subclass to the number of features presented on Xanathar's Guide to Everything. These new features add versatility and the chance to show off which being gave you power.
Each Great Old One has replacement and enhancement features that work similarly to the variant class feature Unearthed Arcana. This allows each warlock to work differently.
Some canonical lore of the Great Old Ones featured on this title.
New Indefinite Madness, based on the Great Old Ones presented here!
- from the publisher's blurb