They just better not kill off ......Khaaan! Oh no! LOL! Anyway I always imagined his consciousness must have merged with the Genesis explosion into an even further evolved being. And he's since, just been chilling 'round the moons of Nibia, beyond the Antares maelstrom, and 'round perdition's flames, on a paradise genesis'ed space-time-dimension-shifted "island", where he's granting people's fantasies.