The Underbase is curated by Boltax within the Temple of Knowledge, and it is off-limits to both Autobots and Decepticons. Acquiring portions of the Underbase can cause enlightenment. The Underbase is so immense that the combined power of its knowledge could detonate a star, and can leave a planet scorched of life. Its energies are especially damaging to Transformer microchips, but not to anything organic.
See Also Underbase Saga