Epic scored a lucky (?) hit with fortnite that brought them a lot of cash but I believe their bread and butter is their game engine where do they charge a perce

Epic scored a lucky (?) hit with fortnite that brought them a lot of cash but I believe their bread and butter is their game engine where do they charge a percentage of the profits. Their store is more of a long-term investment, it might not bring a lot of revenue at the moment but if things go well for them it can easily convert to the top dog.