Gears of War 4 would have cost more than $100 million to make, Epic Games estimated. Anything but a major success would have put the company out of business, co-founder Tim Sweeney told Polygon. The sky-rocketing development costs led the company to sit on the game, ultimately selling off the Gears of War property to publisher Microsoft.

"The very first Gears of War game cost $12 million to develop, and it made about $100 million in revenue," he said. "It was very profitable."

Yet that profit was later mitigated by increasing development costs. 2011's Gears of War 3 cost "about four or five times more" to make than Gears of War did in 2006. According to Sweeney, the way Epic Games was going, the fourth game would have boasted a more than $100 million budget.

Making a profit off the project would have required the game to be a major success. "Anything less could put us out of business," Sweeney said.

Epic Games came to a realization that it had to change its practices in order to preserve the company financially. This was coupled with issues the Gears of War: Judgment community had with the 2013 release. Microsoft rejected Epic Games' plans to fix the problems players had with the game for free. This led to Epic making a shift: First, the studio sold off the Gears of War IP to Microsoft in 2014, following the release of Gears 3. Then, the company moved toward the free-to-play model and updating its current releases instead of focusing on big-budget titles.

"We realized that the business really needed to change its approach quite significantly," Sweeney said. "We were seeing some of the best games in the industry being built and operated as live games over time rather than big retail releases.

Upcoming titles following Epic's change of direction include Paragon, a MOBA, and Fortnite, an indie survival game. Both will be free-to-play games.

For more on Epic Games' "metamorphosis," check out this month's cover story, "Their future is Epic: The evolution of a gaming giant."