Co-founder Tim Sweeney says Epic Games has evolved through four eras. Epic 1.0 is the Epic before Epic. A company called Potomac Computer Systems, which is a fancy way of saying Tim Sweeney working out of his house, stuffing game discs in an envelope and sending them out to people who sent in checks. Still early in its formation, the company manages to snag two top talents: Epic co-founder Mark Rein and 17-year-old wunderkind Cliff Bleszinkski.

Tim Sweeney forms Potomac Computer Systems and releases ZZT.

Tim Sweeney renames the company Epic MegaGames and begins releasing shareware games including Epic Pinball, Jill of the Jungle and Ken's Labyrinth.

Designed by Cliff Bleszinski and Arjan Brussee, Jazz Jackrabbit is one of the first side-scrolling platformers to come to both Mac and Microsoft Windows. It is one of Bleszinski's first major titles.

Epic 2.0 is the era of Epic MegaGames and Epic Games, a company that grew from 15 employees to 25 and saw the need for serious budgets to make big games. It’s a period when Epic teams with publisher GT Interactive to help get its games into more hands. This is the era of the powerful PC, of the original Epic shooter Unreal and of the decision to license the company engine to other developers.

Epic MegaGames releases 3D first-person shooter Unreal, which is co-developed with Digital Extremes and published by GT Interactive. The company also starts licensing the Unreal Engine to other developers.

The company changes its name to Epic Games and moves to Cary, North Carolina.

Co-developed with Digital Extremes and published by GT Interactive, Unreal Tournament shifts the series to focus more on multiplayer gaming.

Epic 3.0 sees a shift away from PC and toward consoles as Xbox 360 shooter Gears of War becomes the face of Epic Games. Unreal, both the engine and the franchise, finds its way onto consoles as well.

Epic kicks off the Gears of War trilogy, developing the first game for the Xbox 360 and Windows PC with Microsoft Game Studios publishing.

Chair Entertainment releases sword-swiping iOS game Infinity Blade. The series goes on to make more than $23 million.

Bulletstorm, developed by People Can Fly and Epic Games, is published by Electronic Arts for the PlayStation 3, Xbox 360 and Windows PC. People Can Fly goes on to work on Gears of War: Judgment.

Epic Games reveals Fortnite, a multiplayer survival game inspired by an internal game jam.

Epic 4.0 is a seismic shift in the company’s path, which redirects it from console games back to the PC. It’s a shift brought on by Sweeney’s recognition of the power of digital distribution and games as services. More than anything, 4.0 seems to have fashioned an Epic Games that has shed its reliance on big, campaign-driven boxed games and an Unreal Engine girded in contracts, for something more dexterous and, Sweeney believes, more appealing to game makers and game players.

China's Tencent Holdings buys 40 percent of Epic for $330 million.

Microsoft acquires the Gears of War IP, opens a new studio and starts work on a new game in the franchise. The new studio, The Coalition, is led by former Epic producer Rod Fergusson.

Unreal Tournament, built on Unreal Engine 4 and developed live with the help of early gamer feedback and Twitch livestreams, is announced. The game's source code is published on GitHub and available to everyone.

Still-in-development survival game Fortnite is announced as a free-to-play title. No release date is given.

Epic announces that the Unreal Engine is now free to everyone, along with future updates. For-profit creations using the engine will have to pay royalties.

Epic Games announces a third-person MOBA called Paragon. The PC and PlayStation 4 game will be free-to-play.

High-end British carmaker McLaren Automotive announces it is using Epic's Unreal Engine to help design and sell its luxury and high-performance cars.