Revan then led the movement to restart the Calendar at 0 once again, but this was heavily opposed in the Galactic Senate and within the Jedi Order. Revan took Malak and a third of the Republic Fleet to the Unknown Regions, where they embraced the Dark Side.
Now Darth Revan, he returned and betrayed the Jedi while searching for the Star Forge, a superweapon. This weapon, and the ever-growing army he was building were bolstering Revan's argument to change the calendar to 0 at the end of the Mandalorian Wars.When Revan's victory over the Jedi seemed certain, Darth Malak betrayed him and seemed to have killed his master. Malak's passion for the Calendar argument was not nearly that of his masters, and the issue was dropped.Revan, now with amnesia, returned and put together the facts of his past, defeated Malak, and got the girl. He took off once more from the known galaxy as his memories returned and probably started a new calendar elsewhere.