Mroon Jassa was a Jedi Master in service some years before the Sith War. Jassa maintained a training compound in the Truuine system on its sole planet of Truuine near its northern pole. Master Jassa spent much of his time training new Jedi apprentices, including the famous Jedi Kith Kark who fought in the Freedon Nadd Uprising.
During Kith's time at the compound, Mroon Jassa was unexpectedly called away for an indefinite period of time. Unfortunately, it is unknown what happened to Master Jassa on this trip, but it is assumed that Master Jassa became one with the Force during its course of events.