The fourth tracked secret in Industrial Zone, the fifteenth level of DOOM II – better known as “Secret 4” – is one of the most enduring secrets in videogame history because it took literal decades to solve properly. The mark of a truly great secret is when only an exclusive few are in on it. There are so many, in fact, that it’s a near-impossible task to pick just five to highlight, so go ahead and share your own favorites in the comments! 1. From Easter eggs and hidden collectibles to entire levels to uncover, each game serves up a hefty helping of rewards for those who venture off the beaten path.
The DOOM franchise is positively bursting with secrets.
