The Expanded Ones

The Expanded Ones (or TEOs) are roughly humanoid beings composed of a translucent blue substance, allowing their bioluminescent central nervous systems to be visible through their flesh. They appear to be perpetually experiencing visibly painful headaches, usually being found clutching their head in pain. They are excellent swimmers and are capable of swimming much faster than the ordinary person, making them a major threat in the oceanic Layer 4.

Levels
TEOs can be found in various "ranks", which they ascend after a very long thinking session. As a TEO ascends to higher levels, its brainpower and physical strength increase, making them much more dangerous. However, they seem to become increasingly apathetic as they level up, with the highest stages almost completely ignoring explorers. Despite this, it is not recommended to interact with them unless absolutely necessary.

Final Brain
Final Brain is a very mysterious phenomenon affecting TEOs that only occurs in Layer 8. Effectively, when low-level TEOs become smart enough, they migrate to Layer 8 to receive a peculiar ‘final brain’. New research on Final Brain has shown one possibility of the outcome: these creatures fuse with the Hole and its purpose, and take the form of something that is desired by someone currently in the Hole. This could explain The Twins, or Dog™, as there is a link between them and the mantra of explorers such as Capt. Rad Foxxo and Shab, Lord of Dab.

STEOs
STEOs (or The Enlightened Ones) are a special class of TEOs who have undergone Final Brain with themselves as their target. This causes a massive boost their entire form, effectively eliminating the agonizing headache that would normally come with extreme power. Only two of these have ever been observed.