His name is Ardyn Lucis Caelum

Noctis is at the facility to save Prompto as the curious man plays mind games. Noctis wields the power of the ring and retrieves his father's sword. The boy band reunites; Prompto reveals his doubt but regains his composure after a friendly reminder. The curious man continues to troll Noctis; he makes it to the crystal, and Ardyn tells a story!

://www.twitch.tv/harryhadouken