[366 Day of Monsters] Day 190/366 - Mythic Cthulhu (Patreon)

“A monster of vaguely anthropoid outline, but with an octopuslike head whose face was a mass of feelers, a scaly, rubbery-looking body, prodigous claws on hind and fore feet, and long, narrow wings behind. This thing ... was of a somewhat bloated corpulence .... it lumbered slobberingly into sight and gropingly squeezed its gelatinous green immensity through the black doorway ... a mountain walked or stumbled.”

— H.P. Lovecraft, "The Call of Cthulhu"

Fighting Cthulhu as a mythic encounter is equivalent to taking on two CR 28 creatures in one encounter. Award a party 240,000 XP for defeating Cthulhu after it uses Unspeakable Form.