Rarin’s “GTA” is a briskly aspirational single — “I been getting all this cash, I don’t need a label/Made it up from nothing fast, yeah this is a fable” — with distorted bass in all the right places.

Earlier this month, Epic Games surprised fans with new experiences within Fortnite such as a new racing game called Rocket Racing, a LEGO-based survival game, and a music game a la Rock Band called ...