Before the war, High Circuitmaster Boltax began storing the accumulated knowledge of the Transformer race in a database called the Underbase. He remained a neutral when the wars between the Autobots and Decepticons began, and his Temple of Knowledge is off-limits to all its participants. It is guarded by his disciples.
It is not known to many that Boltax is no longer a robot, but instead he himself is the Temple of Knowledge; the robot known as Boltax which presides over the estate is merely a puppet.
Marvel Comics continuity
Millions of years ago, when the war on Cybertron was young, an equally young Optimus Prime sought the knowledge of Boltax to aid the Autobots in ending the war. Bringing the Triggerbots with him, he evaded the multiple traps outside the Temple of Knowledge, but was deterred by the Disciples of Boltax. The Triggerbots remained outside, while Optimus Prime continued inside to question Boltax.
Boltax welcomed him but could not give Prime exactly what he sought. Nevertheless, he allowed Prime to bathe in the knowledge of the Underbase in a chamber just beyond where they were standing. Optimus entered, but Megatron and the Triggercons were not far behind. Having already destroyed the disciples, they threatened Boltax as well. Boltax refused them access, and Megatron punched his fist through Boltax's chest, leaving his lifeless body outside the chamber.
In the resulting skirmish, Optimus Prime launched the Underbase off into space, destroying the Temple of Knowledge (the real Boltax), to keep it out of the hands of Megatron. Optimus Prime regretted his careless actions for the millions of years to come, though ironically it made his reputation as a great Autobot warrior.