Yetis are unintelligent robots that are controlled by the Great Intelligence, a being of pure thought from another
dimension. They are its tools on Earth, carrying out physical tasks that either the intelligence or its human agents
cannot manage.
Originally constructed in the Himalayas, the Yetis were given the form of abominable snowmen. They are about 2.1
metres tall, bipedal and covered in long shaggy brown fur. Their red eyes, black leathery snout and yellow fangs
are barely visible through the mass of fur. Yetis look almost comically squat because of the breadth of their
bodies, yet they are dangerous: their hairy hands end in razor-sharp talons, which the Yetis usually slash
violently at an enemy. The creatures have a terrifyingly loud roar.
Human agents control the Yetis about by moving scale models over maps of the local terrain: the models act as a
focus through which the intelligence can channel its Determination to make the Yetis do its bidding.
The Great Intelligence
Exiled from another dimension, the Great Intelligence drifts through time and space, seeking entry into the world of
men. It requires a mental focus in order to materialize: this focus can be the mind of an oriental mystic caught
wandering in the astral plane, or even an active relic of the intelligence's previous visitations, such as a Yeti
control sphere. If its focus is destroyed before it can build up sufficient power to enter the physical world, the
intelligence is temporarily banished. It is theoretically possible to destroy the intelligence in psychic conflict,
but even the Doctor's mind is too weak to contemplate such an action.
Once the intelligence has a human agent, which in effect it hypnotizes and then possesses, it can gather together
the materials necessary to build its robot servants, the Yetis, and their control spheres. A pyramid of control
spheres is sufficient a focus for the intelligence to channel itself through. Its prime human agent gains the
mental abilities of the intelligence.