Markiplier is one of our 2016 Famechanger honorees. For more, click here.

A little over four years ago, Mark Fischbach was studying biomedical engineering at the University of Cincinnati when he got laid off from a mind-numbing job. His mom kicked him out of the house after an argument, so he moved to an apartment, at which point he found out he needed an emergency appendectomy. Then was told he had a fist-size tumor in one of his adrenal glands.

“All this stuff culminated at once,” he says. “I was in the hospital and decided I wanted to do something else.”

Given his lifelong love of video games, he decided he wanted to make action videos “with guns and explosions,” like Freddy Wong’s RocketJump. But then Fischbach found he had a penchant for making videos of himself playing games, right as the trend was taking off. “I wanted to put myself onto the screen 100%,” he says. “I wanted to make sure people saw me for me, and made sure I was being authentic. The way I play videogames with my friends was how I wanted to come across—that’s the style I applied to my videos. I think it’s the camaraderie that people like.”

That’s when he became Markiplier, video-game personality followed by 13.3 million subscribers. Games featured on his channel span multiple genres, with the indie horror title “Five Nights at Freddy’s” representing his most-viewed gameplay videos to date. Markiplier delivers sonorous and excitable narration, sprinkled with a few F-bombs.

Asked what his favorite game is, Markiplier says he can’t single one out. But he allows that ID Software’s new “Doom” first-person shooter released this spring is “wonderful, a really, really creative reimagining of the first one.”

Markiplier has also rallied his fans to donate to his causes. According to Fischbach, viewers have donated more than $1 million to charities including the Depression and Bipolar Support Alliance, Cincinnati Children’s Hospital Medical Center, and the Best Friends Animal Society.

Markiplier is affiliated with Revelmode, a joint venture of Disney’s Maker Studios and Felix Kjellberg (YouTube megastar PewDiePie), which will produce original scripted series starring gaming personalities, as well as games and charity projects. “I think Mark’s appeal heavily lies in the sense of community he has cultivated among his viewers, along with his honest approach to content and his commitment to giving back,” says Courtney Holt, head of Maker Studios.

In 2014, Fischbach, who turns 27 on June 28, moved to L.A., the center of gravity for many in the YouTube community. “Pretty much all the opportunities I was getting were out here,” he says. In addition to gameplay videos, he creates sketch comedy bits and videos where he plays physical games, like when he and his friends raced through a children’s bouncy castle wearing “drunk goggles” while being pelted with water balloons.

“I want to push myself into music and acting—more traditional media stuff,” he says. “If someone wants to make a movie and have me in it, I want to make sure I have the skill set to do it properly.”

Despite being on such a public stage, Markiplier concedes, he’s basically an introvert. “There’s so much I do that I put out there. Sometimes I just like to go to movies by myself and escape,” he says.