SPOILER WARNING: This article contains major spoilers for X-Men Red #5's “Countdown to Extermination” by Ed Brisson, Oscar Bazaldua, Erick Arciniega and VC's Cory Petit, on sale now.
Since coming back from the dead, Jean Grey has assembled her own team of X-Men to make the world a better place for mutants to live peacefully. Part of that involves making new allegiances with the nations of Atlantis and Wakanda, resulting in the introduction of the X-Men Red team's underwater base, Searebro.
It remains to be seen how successful Jean will be in changing the world, but a post-credits scene in X-Men Red #5 reveals the team is still active 20-years in the future. The post-credits scene is the next chapter in the lead up to Extermination, an X-Men event involving the ramifications of the younger, time-displaced X-Men not returning to their original timeline.
Previous Extermination scenes have teased a dark future for the X-Men, as a group of Sentinels have assaulted the Xavier Institute for Mutant Education and Outreach, home of the X-Men Gold team. The original Beast was the first X-Man to fall in battle, but our latest "Countdown to Extermination" post-credits scene, unfortunately, confirms he's not the only casualty.
As Searebro becomes swarmed with mutant-hunting Sentinels, Nightcrawler insists on a hasty retreat. However, Jean uses her telepathic powers to discover the X-Men Gold team failed to defend the Xavier Institute, and are now all dead.
Something to consider is the time-displaced X-Men were also at the school, but Jean doesn't confirm if they count in the death toll as well. The only people Jean calls out by name are Kitty Pryde and Storm. So, there's still a chance her younger self and the remaining time-travelers are still alive.
"Countdown to Extermination" one-page prelude scenes will continue into July, leading to the release of Extermination #1 by writer Ed Brisson and artist Pepe Larraz on August 15.