Jean xmen Jean Grey Finally Evolves Into Her True Cosmic Form: "The Most Powerful Person in Existence"Warning: contains spoilers for Phoenix 5The iconic Omega-level mutant and X-Men hero Jean Grey has a brand-new family and they control the entire Marvel Universe. Phoenix 5 sees the abstract entity known as Eternity welcoming Jean into Marvel's cosmic pantheon, alongside other beings like Eon, the Living Tribunal, and Uatu the Watcher.