Which Epic Games title's post-release game jam helped spark Fortnite?

Gears of War 3's post-release game jam helped spark Fortnite. After Epic Games published Gears of War 3 around 2011, an internal game jam explored ideas that eventually led to Fortnite's blend of construction and combat.

Fortnite was not created as a battle royale game. Its early concept combined the building and resource-gathering ideas associated with games such as Minecraft and Terraria with cooperative shooter survival inspired by titles such as Left 4 Dead. Players would construct defenses and fight waves of monsters.

The project then went through a long and difficult development period. Epic moved it from Unreal Engine 3 to Unreal Engine 4, expanded its role-playing elements, changed its visual style from dark and gritty to colorful and cartoon-like, and shifted toward a games-as-a-service model.

Battle Royale came much later, after PUBG's success in 2017. That mode transformed Fortnite from a long-developed cooperative project into one of the industry's biggest live-service games. The game jam was therefore the starting point for Fortnite's broader foundation, not the moment Battle Royale was invented.