MrBeast, whose real name is Jimmy Donaldson, became known on YouTube for insane stunt videos as well as his philanthropy. He's revealed several times throughout the years most of the money he makes from YouTube, including from ads and sponsors, goes back to help him create more videos.
Due to the immense popularity of his challenges (and the fact that he gives away boatloads of cash), MrBeast has now overtaken PewDie as the most subscribed YouTube channel.
MrBeast celebrated reaching 100 million subscribers by giving away a private island. Now that he's achieved what most believed impossible, MrBeast might end up buying Earth and giving it away.
All jokes aside, PewDiePie is very encouraging of seeing MrBeast surpass him. Earlier in the year, PewDiePie found out that he was in danger of losing his spot as the most-subscribed YouTuber.
If you told him this a few years back, PewDiePie might have started a subscriber war with MrBeast. Instead, he seemed content with what he's achieved already and that he can't wait for MrBeast to surpass him in terms of subscriber count.
At the moment, MrBeast and PewDiePie are still the only individual YouTubers to hit the 110 million mark (and even the 100 million mark).
Given that MrBeast doesn't seem to be showing signs of slowing down anytime soon, he'll likely be the first to reach 120 million subscribers and widen the gap between himself and the other content creators.