Bethesda are celebrating the 20th anniversary of the release of Wolfenstein 3D, the classic first person shooter from id Software that originally came out on May 5, 1992, launching a free browser-based version of the game and releasing a podcast video of John Carmack, the game’s lead programmer, commentating on the game while playing the original DOS version.

The game has previously been re-released for iPhone, iPad and iPod Touch, and these versions will also be offered for free for a limited time.

Few gamers over a certain age won’t have played this game before, and jumping back into it you can see immediately why it was so popular.

Check out the embedded podcast video below, or go here to play for yourself.