After nearly 24 years of demon-blasting fun, one fan has discovered the final secret of Doom II. These days, gamers spend hours on end collecting every last trophy and finding every Easter egg, so imagine the frustration of not being able to complete a game for over two decades.

Originally released for the MS-DOS in 1994, Doom II followed in the footsteps of its predecessor and became one of the biggest games of the decade. Taking the leading Doomguy from Mars and to the apocalyptic expanses of Earth, Doom II was the bigger and bloodier brother of the original. For the first time in Doom II's acclaimed history, gamers can now celebrate 100% completion without the use of cheats.

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Discovered by YouTuber Zero Master, Doom co-creator John Romero posted on Twitter and confirmed that the door to the game's last secret has finally been unlocked. As well as sharing his congratulations, Romero went on to explain how it's done:

Since Doom II's debut all those years ago, fans have spoken about the last of the 10 secret areas in the Industrial Zone. While uncovering it has never been a problem, activating the secret area without using cheat codes has always evaded players. According to Zero Master and Romero, Doomguy has to be pushed into the teleporter by an enemy to be transported to the final secret. As the video shows, Zero Master was involved in a game of cat and mouse as they used a Pain Elemental to nudge them to the teleporter.

The hidden secret has been lost for so long, even some Doom experts had thought it was a glitch in the game's code. As Romero points out, he has always known how to unlock the final piece of the puzzle and was simply waiting for someone to figure it out. The co-creator's words echo some pretty impressive skills from Zero Master. Whether it was simply a fluke or a well thought out plan of attack, Zero Master can claim the title of being the first person to finish Doom II the way it was intended.

Although old games are littered with hidden secrets that have stood the test of time, Doom II can be officially added to the list of titles that have been 100% completed. Coming soon, Doom Eternal will again bring Hell to Earth as id Software works on a sequel to 2016's reboot. Doom Eternal has already shown off some impressive gameplay at this year's QuakeCon, and boasting the biggest Doom to date, is sure to be jam-packed with hidden secrets for gamers to uncover.

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Source: John Romero