Anarchitect

The Anarchitects were disemboied weapon intelligences used by an enemy of the Time Lords and were used on an assault against Gallifrey.

These creations acted like computer viruses that were able to inhabit architecture and rewrite it allowing them to rebuild entire cities at will. This technology was the same used by the early TARDIS models and were within the scope of the Gallifreyans but were never considered as weaponof war. They were able to infect walls and loors but individuals were safeif they were in a river.

Lord Ruthventracolizabaxil starved to death in his own TARDIS when an anarchitect hijacked it and turned the central corridor into an endless mobius loop. (EDA: Alien Bodies)