# Marvel X-Men integration in Avengers: Doomsday

> Live situation record from CLSTR: https://clstr.news/situations/marvel-xmen-integration-in-avengers-doomsday
> Updated: 2026-08-14T18:06:12.000Z. Sources: 11. Developments: 4.

In July 2026, Marvel used San Diego Comic-Con to announce two major casting returns for its upcoming film *Avengers: Doomsday*. Actress Rebecca Romijn confirmed she will reprise Mystique, noting a more natural shooting experience and balancing the role with her work on *Star Trek: Strange New Worlds*. A week later, actor James Marsden revealed he will return as Cyclops, describing the costume as “super special” and stressing his long-standing desire to revisit the character. Both announcements underscore Marvel’s strategy of weaving X-Men characters into the broader Avengers cinematic universe ahead of the film’s planned December release.

In early August, Marvel disclosed that *Avengers: Doomsday* will feature updated X-Men costumes that more closely follow the original comic-book designs. Mystique’s look will shift from the blue, scaly makeup of the Fox era to a white costume with gloves, boots and the signature skull-belt, while other characters such as Professor X, Magneto, Cyclops and Beast also receive faithful redesigns. The visual changes address fan criticism and reflect the MCU’s broader push for source-material fidelity.

Following these updates, the D23 convention in Anaheim provided a more detailed look at character costumes and props. Exhibits showcased Mystique’s classic white regalia, including long sleeves, pants, and a small tiara, alongside Nightcrawler’s ensemble, which features a long coat with the X logo, a waistcoat, pinstriped pants, a turtleneck, and dual cutlasses. Other displayed items included a large Sentinel head with glowing green eyes and a purple helmet, a sign for Xavier’s School for Gifted Youngsters, and various hero costumes such as Red Guardian’s tracksuit and Shuri’s Black Panther suit.

## Timeline

### 2026-08-14: D23 reveals Avengers: Doomsday costumes and props

Costumes for Mystique and Nightcrawler, along with various Marvel props, were revealed at the D23 convention for the upcoming film Avengers: Doomsday.

2 sources. https://clstr.news/cluster/d23-reveals-avengers-doomsday-costumes-and-props

### 2026-08-07: Marvel's Avengers: Doomsday Updates X‑Men Costumes After 26 Years

Avengers: Doomsday, due December, revives classic X‑Men with comic‑accurate costumes, notably giving Mystica (Rebecca Romijn) a white outfit, correcting a 26‑year design criticism.

2 sources. https://clstr.news/cluster/marvels-avengers-doomsday-updates-xmen-costumes-after-26-years

### 2026-07-29: James Marsden to Return as Cyclops in Marvel’s Avengers: Doomsday

James Marsden will reprise Cyclops in Marvel’s *Avengers: Doomsday*, announced at Comic‑Con; he said he always hoped for a return and discussed the role with Kevin Feige.

2 sources. https://clstr.news/cluster/james-marsden-to-return-as-cyclops-in-marvels-avengers-doomsday

### 2026-07-22: Rebecca Romijn Returns as Mystique in Avengers: Doomsday

Rebecca Romijn will reprise Mystique in Avengers: Doomsday, citing greater confidence and ownership of the role after past challenges, while also starring in Star Trek: Strange New Worlds.

5 sources. https://clstr.news/cluster/rebecca-romijn-returns-as-mystique-in-avengers-doomsday

---
Cite as: Marvel X-Men integration in Avengers: Doomsday. CLSTR, https://clstr.news/situations/marvel-xmen-integration-in-avengers-doomsday