The Boomsday Project is Hearthstone's next expansion

Hearthstone's next expansion has been revealed—and it will look familiar to long-time players.

The Boomsday Project is the game's newest card set, and will release on Aug. 7. It was revealed in a YouTube video on the official Hearthstone channel which was unlisted and removed within an hour. It hadn't been promoted on any social channels or website, suggesting this might have been revealed a tad early. The website URL in the description, theboomsdayproject.com, is currently not live.

The Boomsday Project is a science and research facility run by Dr Boom. You might remember him—he was that super powerful legendary you grew to hate from Goblins vs Gnomes.

The trip down memory lane doesn't stop there. The cinematic features both goblins and, yes, gnomes as well. So in some ways, this sort of seems like a revisit of that expansion. This would be the first time Blizzard has gone back to a theme in any way, and could mean multiple new Mech tribal cards being added for the first time in a long time. Currently there are only three Mech cards outside of the Classic set in the Standard format.

Dr Boom will also likely be returning in a new form, but we've seen that before with characters like Elise and Hemet.

Card reveals will start July 23 with the traditional kickoff livestream. Following the most recent timetables expect cards to be unveiled daily for a fortnight before the expansion release week.

The 50-pack bundle pre-order returns with a cardback, but this time there's a second pre-order—the 80-pack mega bundle. That includes the card back, a random golden legendary, and a new Warlock hero portrait, Mecha-Jaraxxus. No pricing has been revealed.