The Well of Blind Souls is one of the most frightening realms imaginable to a mage. It is a kind of immense paradox dimension, final Quiet or hell where those who strayed from the path of Ascension are held until they succumb to Descension and Oblivion completely. It is the end of Ascension.
Physically the Well is just a infinitely deep (and high) well of black, wet, nitrous stone with a narrow staircase without railing running around it in a great spiral. It is maybe just a few meters across, but somehow it seems to be immensely larger. And the abyss below seems to draw everybody closer to the edge, enticing them to jump into its welcoming embrace. Everything seems to be drawn towards the edge and oblivion, as if gravity was slightly slanted.
At irregular intervals small doorways appear in the stone, hardly more than cracks in the walls. Each opening leads to a small paradox dimension, containing a mage or other being trapped here. Some are open, other locked in various ways. In these realms no real time ever passes, and the inhabitant can never die. The only way to get out is to return to the path of Ascension or to give up completely - in which case the well will claim the victim. Unlike normal paradox dimensions, which just seek to enforce the laws of static reality and will release their prisoners when they have learned their lesson, the well seems to be more a prison and will not voluntarily release a victim unless he or she is able to return to the path of Ascension - but the well will do its best to prevent this using all available means.
In one of the realms Giorgios Theophilus (the famous bacchant) is tormented by his own actions. He had used Life to become truly dazzling and eternally young, but finally Paradox caught him and he was ripped into the well by a horrible backlash. The backlash cut out his tongue, his hands, his feet, his genitals, his eyes and his ears and deposited him within a tiny realm filled with mud and pigs. The pitiful remains of Giorgios have to fight against the pigs to get the awful garbage that is his only food.
Another realm is an immense warzone, a huge industrial complex of rusting and burned machines where robotic warriors fight each other in an eternal war. There are mines, hidden gun turrets and surveillance cameras everywhere, ready to bring fire and death to anybody moving carelessly. But nobody can die here, and if a person is seriously maimed the technological garbage in the vicinity will painfully crawl into him, and replace the destroyed parts with makeshift bionics. A short while later he will be ready for the fight again, now even deadlier. Even fragments of flesh splattered by gunfire onto the walls are integrated into the rusty networks of electronics and linked with infrared cameras. There is no end to the carnage and pain here, just the will to survive a few moments more.
One realm is an immense mirror labyrinth where a Verbena frantically seeks the real reflection of herself. In another a Hermetic mage is locked into an endless game of chess as a game piece. There are also stories about a failed Oracle imprisoned somewhere deep in the well, trapped in a realm of such subtlety that it cannot be distinguished from reality.
The true nature of the well is conjectural, but it seems to be a manifestation of the concept of Descension, the flight from the true path to Ascension. It is probably normally located in the darker reaches of the High Umbra, but it can manifest anywhere it chooses to claim a victim. But even more importantly, it is able to draw mages towards itself when they begin to loose their footing on the Path; at first subtle dreams manipulate then, then strange coincidences enticing the mage to stray from the path begins, then a growing obsession and finally the descent into the well to seek out a realm.