The first two Doom games are well known for their use of keycards as a means of player progression. Every level forced the player to explore and find a yellow, red, and blue keycard, each of which would open anything from a secret room to the pathway towards the exit. This design is just as synonymous with Doom as the demons or the chainsaw, which is why it is no surprise that they are confirmed to be back. However, depending on whom you ask, this is either a call for celebration or condemnation. For many, the keycards were a source of frustration that sapped the games of their pacing. A case can be made that their use is too antiquated and outdated for modern gaming. Luckily, id Software is aware of this, and has stated that their use will be more spaced out. Its unlikely that the new Doom's levels will be quite as long-spun and labyrinthian as the originals, which means the keycards wont be quite so ponderous to find either. It appears that the keycards are there more as a callback to the originals; another sign of good faith that Doom hasnt forgotten its roots as it strives to make its way in the modern gaming landscape.