Known as the Excession at Voi by the scientific community or more commonly as the Portal or Artifact by the general UNSC public, the Excession is a massive Forerunner still-operating relic underneath New Mombasa, Kenya on the continent of Africa. The Excession was designed to generate a slipspace portal four kilometers above ground level which linked to a small Forerunner probe twenty eight million kilometers from the main arms of Installation 00, the probe forces the slipstream rupture to remain open allowing slipspace-worthy craft to return to their point of origin. The Excession hidden under New Mombasa on Earth was constructed by huge Stato-Sentinels under the command of the Forerunner known as Librarian, who appears in many recovered texts on Forerunner databases and was hidden before