Supplement V: Carcosa

From the designer's website:

Supplement V: CARCOSA is a book of rules options for the original Dungeons & Dragons game published in 1974. CARCOSA includes:

• a new character class: the sorcerer who summons and controls Cthulhoid entities
• a new form of magic, including 96 sorcerous rituals
• an easy-to-use psionics system
• dice conventions
• 48 new monsters
• tables for the random generation of spawn of Shub-Niggurath
• 5 colors of the desert lotus
• countless high-tech weapons and items of the Space Aliens
• Random Robot Generator
• technological artifacts of the Great Race and of the Primordial Ones
• mutations
• 400 encounters on an outdoor hex map with an area of 34,880 square miles
• and more...