In honor of Fox's X-Men Day, writer Chris Claremont and writer-editor Louise Simonson appeared in a video featurette to explain the power and appeal of Dark Phoenix's titular character Jean Grey.

In the Marvel Icons video, the legendary writer and editor reminisced about their days working on Uncanny X-Men and explained what it is that makes Jean Grey such a compelling character. As a writer, Claremont always had a clear vision of how he would develop the story of Dark Phoenix. According to him, the most interesting part of Jean Grey's story is exploring how a character with such immense power would handle it. "Dark Phoenix is the ultimate expression of the darkest shadow in everyone's soul," Claremont concluded.

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Simonson agreed with Claremont and explained their history of working on the series together. The focus was all on the characters, and Claremont and Simonson positioned Jean Grey as the heart and soul of the team. The difficult situations and decisions Jean had to face made the character the writer's favorite.

The duo also shared their memories of Stan Lee, who originally co-created Jean Grey with Jack Kirby in 1963 for The X-Men #1. Claremont and Simonson explained that Lee's motto about actions having consequences was an important guideline for scripting Jean Grey's character arc.

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The Marvel Icons video also shows material of Jean Grey both from the character's history and the upcoming movie, which debuts next month. In addition to this Claremont and Simonson video, X-Men Day features other exclusive X-Men content, special events and advance ticket sales for Dark Phoenix.

Directed and written by Simon Kinberg, Dark Phoenix stars James McAvoy as Charles Xavier/Professor X, Michael Fassbender as Erik Lehnsherr/Magneto, Jennifer Lawrence as Raven Darkhölme/Mystique, Nicholas Hoult as Hank McCoy/Beast, Sophie Turner as Jean Grey/Phoenix, Tye Sheridan as Scott Summers/Cyclops, Alexandra Shipp as Ororo Munroe/Storm, Kodi Smit-McPhee as Kurt Wagner/Nightcrawler, Evan Peters as Peter Maximoff/Quicksilver and Jessica Chastain. The film arrives in theaters June 7.