The Tower is the secret structure of the Aurbis, which is a wheel turned on its side. This secret was allegedly discovered by Lorkhan during the creation of Mundus, and is claimed by Vivec and Mankar Camoran to be a pre-requisite for CHIM.
The Tower as the Structure of the AurbisEdit
The Aurbis is referred to by some as structured like a wheel, with "the Eight gift-limbs of SITHISIT" as the spokes, and leaving sixteen spaces between the spokes. When viewed sideways, this is the Tower, which is the Aurbis seen from the outside. This seems to be the case regardless of the state of the cosmos within the Wheel.
The Secret TowerEdit
The Triangular Gate is, according to Sermon 21, held by the "heart of the Serpent," likely a reference to Lorkhan. Due to its location within the heart of the Serpent and its connection to Lorkhan, the Secret Tower is likely to be within Mundus. This is reiterated in the Commentaries on the Mysterium Xarxes, where Mankar Camoran states: "First Tower Dictate: render the mutant bound where he may do no more harm. As God of the Mundus, alike shall be his progeny, split from their divine sparks. We are Eight time eight Exarchs. Let the home of Padomay see us as sole exit."
The ultimate secrete of the Secret Tower is that the self is divine, which is potentially the ultimate purpose and mirror of the structure of the Aurbis. This is also potentially the secret required for the attainment of CHIM.
Out-of-Game Text Elaboration on the Secret TowerEdit
The exit spoken of implies that escape from Mundus is only possible through Mundus, that is, the Triangular Gate. It is also stated in other sources to be the "circle within the circle," where the reflection of of the universe's structure can be clearly seen.[OOG 1] By this reasoning, it is impossible (or at least unlikely) for non-mortals to use the Walking Ways to Godhood which involve the Tower, because they do not view it from a place of confinement. Conversely, those with CHIM are described as "[residing] within" the Secret Tower.[OOG 2]
Due to the triangular nature of the gate, this is also possibly linked to the concept of the Enantiomorph, which involves three participants. The Thief and the Tower are connected to this when Hasphat Antabolis claims that, "The Thief is another metaphorical absolute; in this case, he represents the 'taking of the Tower' or, and sometimes more importantly, the 'taking' of the Tower's secret."[OOG 1] If this is the case, then the enantiomorph (in which the Thief is identified with the Rebel, the ultimate victor of enantiomorphic conflict) can be seen as a vital part of understanding and finding the Secret Tower.