Xbox has started showing Mythic Achievements to members of the Xbox Insider Program, a profile marker earned by completing every original achievement in a game, and it has been applied retroactively. Xbox Wire says the early look opened on September 29 and that eligible Xbox 360 titles are included.
This is an Insider feature, not a general console update. The post gives no date for a wider rollout, and it attaches no Gamerscore to a Mythic Achievement.
Xbox bills it as one of its most player-requested features.
How you earn Xbox Mythic Achievements and what does not count
The trigger is completing all of a game’s original achievements. Anything added later through DLC or updates is not required, and once Mythic status is earned, Xbox Wire says “it’s yours to keep”.
Xbox Wire describes the feature as “a new way to celebrate the games you’ve completed and the milestones you’ve earned along the way”.
Later additions are tagged “add-on” in the achievement list, so the original set stays identifiable.
A progress bar at the top of each game’s achievement list shows how close you are, with an option to narrow the view to the original achievements you still need.
The retroactive pass is the part that lands without you doing anything. Mythic Achievements “have already been added to eligible games you completed in the past, including XBOX 360 titles”, Xbox Wire says.
So a profile can pick them up before its owner next turns the console on.

What the new Gaming tab adds to your console profile
Profiles now carry a Gaming tab holding your achievements, your next Gamerscore milestone badge and the games you have completed.
Mythic entries stand out in the achievement history with what Xbox Wire calls “a heroic frame”, which is the whole of the reward so far.
Friends’ Gaming tabs are visible too, so the comparison is built in. The same progress information turns up elsewhere on the console, including in the Guide and in achievement details.
No Gamerscore, no unlock and no store credit attaches to Mythic status in anything Xbox has published.
Why Xbox Insiders see this before the rest of the install base
The Insider Program is where console dashboard changes get tested, and the wording here is an “early look” rather than a release.
Joining is opt-in, so the audience is self-selected and small next to the install base, and anything in an early look can change before it ships.
The way in is the Xbox Insider Hub, which runs on Xbox Series X|S, Xbox One and Windows PC.
New completions count the same way as old ones, whether that is an Xbox 360 game finished a decade ago or one of the 20-plus Xbox games arriving between October 6 and 9.
Xbox Wire gives no general release date for any of it, so everyone outside the Insider Program waits.