Duke Nukem Forever (2001)

Before being officially released in 2011, Duke Nukem Forever had demos and promotional images and videos released to the public, which had gameplay different from what ended up being released, since the game went through a 14 years long development hell and technology changed during this period. The build from the 2001 E3 that was leaked online in May of 2022, and it's one of the most known pre-release versions of the game.