The Ivory Prince, or Hellebore, was a Constellation-Class ship used by Horizon during the Time of Fables. It accompanied Perennial to the centre of the galaxy, where its crew helped install her in the space station there, giving her the power of the galactic core. During this time, it also held off the Divine Empyrean and the forces of Stel Nideo.
Thousands of years later, it was briefly summoned or recreated by Perennial as part of the trials of the Witch in the Glass.