On the gaming side of YouTube, one of the superstars alongside Jacksepticeye and PewDiePie, who greatly contributed to the genre’s mainstream recognition, is none other than Mark Edward Fischbach, aka Markiplier. Throughout his extensive career in the industry, Mark has established a highly esteemed reputation for himself to the extent that even AAA games paid tribute to his influence in various ways.

Among the numerous Easter eggs and in-game tributes Mark has received over the years, none could compare to the immense joy and heartfelt warmth he experienced when Doom Eternal, the action masterpiece of 2020, honored not only Mark but also his beloved father through a meticulously crafted in-game detail.

Markiplier moves to tears by Doom Eternal’s Easter egg

Within Slayer’s home base, players have a multitude of areas to explore. However, one particular bookshelf undoubtedly captures their attention. Despite Doom’s serious themes, the game doesn’t take itself too seriously. This is made apparent by the bookshelf, which is filled with classic literature and comic books.

Among the array of book titles adorning the shelves, one stands out prominently: “How to Groom Your Mustache,” authored by Clifton M. Fischbach. At first glance, one might perceive it as just another humorous title among the various Easter eggs present. However, eagle-eyed Markiplier fans may understand the true hidden significance behind this book.

Clifton M. Fischbach, Mark’s father, sadly passed away in 2008 but played a profound role in Mark’s life. It was Clifton who introduced Mark to the DOOM series during his early years, fostering a deep connection to the game from a young age. As a heartfelt tribute to his late father, the developers included the book in the game.

“My dad died of cancer on July 4 of 2008, so it [the disease has] affected me personally. He [my dad] was the guy who raised me. My parents divorced at young age, so me and my brother were with our father. He died of lung cancer,” said Markiplier once. Making the Easter egg’s significance even more special.

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“How to Groom Your Mustache” by Clifton M. Fischbach, found on the bookshelf within Slayer’s home base, is an emotional journey for every fan, particularly for Mark himself. Mark shared that his father had an impressive mustache, which served as inspiration for the book’s title. He had shared this fact with the game developers, but he never imagined they would immortalize his father in their game as a reward for his contributions.

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What do you think about this absolutely heartwarming Easter egg? What is your favorite Easter egg in the game? Let us know in the comments below!