Fortnite added Peter Griffin from Family Guy recently, and if you can push past the existential dread that sentence may give you, it's a no-brainer. Once a PvE co-op builder, Fortnite's battle royale game mode has long outgrown its humble roots and become an 'Oops! All Franchises' monolith.
"I had to have somebody explain to me what the fuck Fortnite is," MacFarlane says—like a man discovering the McDonalds of an alien planet. "And then I said 'well that sounds kinda cool! Yeah, why not, let's do it.' That's a lot of what my career is, somebody explaining to me: 'how about this' and I say 'what's that?'"
I decided to absolutely decimate my YouTube recommendations for the foreseeable future by looking up whether Family Guy has made a Fortnite joke and, sure enough, there've been a couple of throwaway gags, one where Stewie says he's going to watch the older boys play Fortnite in an electronics store—and another where Joe says he "levelled up in Fortnite", which does sound like something someone who doesn't play Fortnite would say.
Granted, Seth MacFarlane doesn't write every episode of Family Guy—nobody deserves that—and the show itself occupies the territory of 'must reference current thing'. I completely believe him when he says the game passed him by. His admirable ambivalence to battle royales also manifests when he talks about Peter's muscular physique: "I was told that they didn't have the budget to create his actual body".
Not to detract from the character's size, but the issue probably lies less with the rendering of Peter Griffin and more with how much the game's standard moveset would prove a clipping nightmare for his body. No developer team is going to create a whole set of new animations for one character, not even for Peter Griffin Fortnite.
Still, this is a pretty good measuring stick of how popular the game has become. While you might think snagging the licence to use a character in a game is hard—and you'd be right—it's staggering that Epic Games were able to approach MacFarlane and get him to agree to using one of his most recognisable characters, despite him having zero investment in the game whatsoever. Luckily, there is now a Family Guy.