Xbox Mythic Achievement Leak: How the Platinum-Style Reward Could Work

A possible Xbox completion reward called Mythic Achievement has surfaced in Xbox PC app code. The findings suggest it could recognize completion of a game’s original achievement set, but Xbox has not formally announced the feature or confirmed its rules. The distinction matters: leaked app code can offer clues, but it is not the same as a public product announcement.

The discussion follows an August post from Xbox CEO Asha Sharma. In a conversation about a Platinum-style reward for finishing a game’s achievements, Sharma said the team was working on something for later in 2026. Her post did not name Mythic or specify how the feature would work.

What the Xbox app code appears to show

XCT.live’s analysis of Xbox PC app version 2610.1000.53.0 found Mythic-related text, an unlock notification, a badge, an animation, and a sound asset. The app code also appears to group achievements under a “BaseGame” category and to identify other achievements as “Add-on.”

Based on that code, XCT.live’s interpretation is that Mythic could be awarded for completing all achievements in a game’s original set. The analysis says this would count achievements in the group rather than total Gamerscore, with add-on achievements outside the base group. Those are interpretations of unreleased app code, not rules Xbox has confirmed.

Would DLC achievements count?

The current code analysis suggests DLC achievements labeled “Add-on” would not be part of the Mythic requirement. It also indicates that the Xbox app expects to receive the relevant achievement groups from Xbox services. Which achievements belong in each game’s base group would therefore depend on data provided by Microsoft.

That leaves important details unresolved, including how the feature would handle title updates, older games, and progress already earned by players. XCT.live reported that, at the time of its September 23 check, the app feature flag was off and its requests were not receiving achievement-group data from the server.

Is Mythic Achievement officially confirmed?

No. Xbox has not formally announced Mythic Achievement or shared a release date. The August teaser indicates that Xbox was working on something related to a Platinum-style completion reward, while the name, badge, and possible rules have come from app-code analysis and reporting.

The screenshot above shows existing achievement tracking for Sea of Thieves. It is included as an example of the Xbox game-hub context, not as evidence that the Mythic feature is live or enabled for that game.

Xbox Mythic Achievement: frequently asked questions

Has Xbox released Mythic Achievement?

Xbox had not announced or enabled it in the app data checked by XCT.live on September 23, 2026.

Would Mythic mean 100 percent Gamerscore?

The code analysis points to counting achievements in a BaseGame group rather than calculating Gamerscore. Xbox has not confirmed the final rules.

Would players need to complete DLC achievements?

XCT.live’s reading of the app code suggests add-on achievements are separate from the BaseGame group. The final eligibility rules remain unconfirmed.

Will the reward apply to games players already completed?

The available app-code analysis does not confirm how existing completion progress would be handled.

Sources: Pure Xbox’s report, XCT.live’s Xbox app code analysis, and Pure Xbox’s report on Asha Sharma’s August teaser.