The M'and Ybula are a fictional race created by Chaosium in 2013 for the Call of Cthulhu RPG.
The M'and Ybula are a race of Deep One/Human hybrids. Intelligent and powerful cephalopod humanoids which were created by the Deep Ones to serve and protect the imprisoned Star Spawn Whose eternal prisons had been elevated far above the sea level by tectonic activities over the millennia. The M'and Ybula have adapted to living on the Tibetan plateau, living close to the salt lakes of Tibet. Over millions of years their numbers have dwindled. As they age at a far slower rate than any other lifeform on Earth, the eldest of them possess great intellect and powerful spells. It's a sophisticated race which is in contact with humans and likely other Mythos races. The M'and Ybula understand and use technology, but prefer using magic. It's rumored that their greatest weapon is an Elder Thing weapon they have somehow acquired. A virus which was developed by the Elder Things to eradicate all humans and shoggoth, and which is their doomsday weapon. One that has been used to threaten mankind when they need to force one of their nations or leaders to do their bidding. The oldest and wisest are shapeshifters able to take many forms, including that of human beings.
Unknown to the younger members of the race, the eldest also have the ability to preserve their lifeforce and thoughts for days if their physical form is killed. During which their "spirit" is able to look for a new host, normally a human baby. Which will grow like a normal human but with the knowledge and thoughts of the M'and Ybula. Once it becomes an adult, it will take full control and either continue existing as a human for a time or manipulate the body's DNA to transform it into a M'and Ybula. M'and Ybula are naturally stealthy beings and are able to camouflage themselves in a manner similar to cuttlefish. Ancient M'and Ybulas usually are entrenched in mountain fortresses or cavern systems, where they surround themselves with their minion, servants, and slaves (the latter two consisting of humans). Within some of these enclaves are elaborate bureaucracies and their inner circles are rife with Machiavellian politics. The M'and Ybula that walk the land as humans for years do so for a variety of reasons. Some of them enjoy inflicting pain and fear on humans via torture. Others have a clinical mindset, seeing humans as subjects to perform experiments on. Some enjoy mankind's sensual pleasure, engaging in all types of pleasurable and painful activities.