Doom: Eternal is all about secrets, and there are plenty in the game for those looking to uncover anything interesting left behind by developer id Software. You can locate the standard secret found in the levels, such as the slayer gates, albums, cheat codes, or toys. But you can also find one on the bottom of the hub ship, the Fortress of Doom.
On the Fortress of Doom, you want to go down to the second level of the structure where the Doom Guy’s private room is. It contains all of the weapons you use during your journey, all of the toys you acquire, and it features several heavy metal guitars on the right side of the room you can admire. Closer to the back, you can find a computer you can freely access and it asks you to input a code for two different files. Go to the file on the right.
The code you want to input is: FLYNNTAGGART. After you type in the proper code, you will have immediate access to the original Doom 2 game. You can freely play it from that computer station as much as you want, providing a great break from the high-octane experience of Doom: Eternal. The little easter egg is an interesting way to promote the game and allows players to try out the original game without having to find a way to purchase it.
There are plenty of other secrets in Doom: Eternal. Keep your eye out while exploring all of the game’s levels to locate them, and make sure you spend a little time exploring each level.