For the past five years, Call of Duty fans on PC have had to rely on Blizzard's Battle.net app to purchase the latest games in the series. Starting with Call of Duty: Black Ops 4, all games and services for Call of Duty have been Battle.net exclusive for PC to avoid Steam and other storefronts' fees. That may be changing soon, however. There's new evidence indicating that Call of Duty could be coming back to Steam with the upcoming release of Call of Duty: Modern Warfare 2.

Call of Duty fans recently explored the franchise's profile on Steam. While recent Call of Duty games haven't been released through the PC storefront, all games from Call of Duty: WW2 and back remain available for purchase. At the bottom of this profile was a surprising graphic. It's nothing complicated, just a link back to the Call of Duty franchise portal on Steam. Yet within the image is a piece of art from Call of Duty: Modern Warfare 2, concept art of Simon "Ghost" Riley.

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After the art was discovered and shared online in various Call of Duty communities, it was quickly removed and replaced with a blank blue graphic. Without official comment on the matter, there's no way of telling exactly what it means. Obviously, it was uploaded by accident. Whether it was accidentally uploaded too early and indicates a forthcoming Steam release for Call of Duty: Modern Warfare 2, or if the art was used accidentally and it means nothing remains to be seen.

The evidence at hand isn't substantial, by any means. There's no confirmation or firm evidence of Call of Duty: Modern Warfare 2 being released on Steam. But what's there is eyebrow-raising, at the very least. A graphic featuring Call of Duty: Modern Warfare 2 art being uploaded to an official Steam page is no small matter.

Call of Duty returning to Steam is not an impossible decision, by any means, but it would be surprising at this moment. What would make sense is if Microsoft's acquisition of Activision Blizzard were to complete and then Call of Duty was brought back to Steam. Microsoft has done similar for many of its major game releases in recent memory. But Activision has shown no indication it wants to do so, yet.

All Call of Duty fans on PC can do is wait for more information at this point. More Call of Duty: Modern Warfare 2 news will be coming relatively soon since the game is planned to launch later this year. Steam support wouldn't likely be made into a huge announcement, but it would nevertheless prove meaningful to PC gamers.

Call of Duty: Modern Warfare 2 releases on October 28.

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