The Sun Cage Anomaly was an Anomaly linking the Sun Cage in the Late Holocene epoch to the Eocene epoch. It stayed linked to the Sun Cage wherever it went because of the fact that the Sun Cage was made of magnetite, which has strong magnetic properties.
Ancient Egypt Incursion
The Anomaly opened up in Ancient Egypt on the west bank of the Nile. A Pristichampsus came through, and was worshipped by the Ancient Egyptians and incorporated into the mythology as the demon goddess, Ammut. The Ancient Egyptians also found the Anomaly, which they mistook for a piece of the Sun. When they discovered it was magnetic, they built the Sun Cage around it out of magnetite in order to contain the Anomaly. Because of magnetite's magnetic properties, the Anomaly stayed linked to the Sun Cage wherever it went, even after the Anomaly closed.
In 2009, by which time the Sun Cage had been moved to the British Museum, taking the Anomaly with it, the Anomaly reopened and a Pristichampsus came through and went on a rampage in London. Later, when another Pristichampsus tried to come through and attacked Connor, it bit an electrical light, electrocuting itself and the Anomaly and causing the Anomaly to lock for a few seconds. Eventually, the Pristichampsus returned through the anomaly, which then closed. The Sun Cage was later moved to Pyongyang, presumably taking the Anomaly with it.
- It is unknown how this Anomaly stayed linked to the Sun Cage while it was closed, as while the Anomaly was closed, its magnetic field (which was what kept the Anomaly linked to the Sun Cage wherever the Sun Cage went) would have gone.