40. Lemmings (DMA Design, 1991)
A popular puzzle game that spawned a horde of rereleases, updates, sequels, expansions, clones and parodies, Lemmings is a simple concept - get a quota of Lemmings safely to the goal. To this end, one picks a few out of the crowd and assigns them jobs meant to help the others avoid danger or bypass obstacles - whether simply stopping and forcing them to go the other way, digging through dirt, climbing up walls, or blowing themselves up to clear an obstacle from the others' path. Once enough are safely through the exit door, the next stage begins. Simple enough concept, but many of the later stages get deviously difficult, requiring some very fast thinking to succeed. Given just how prolific and popular the series was, if you owned basically any platform out in the early '90s, you probably played or at least saw Lemmings or one of its sequels/spinoffs/expansions at some point. And thankfully, all of them were pretty damn fun.
39. Descent (Parallax Software, 1995)
A relatively unique take on first person shooting action, Descent was basically Doom put into the third dimension - you controlled a spaceship that could move and strafe in any direction and were set in a maze full of various robots and traps, tasked with rescuing a number of hostages, blowing the reactor and escaping before the whole place goes up. It was a bit hard to adapt to (especially if you didn't have a flight stick handy and had to make do with a mouse-keyboard setup), but it was visually impressive for the time and it played great once you adapted to it. The later levels do tend to get aggressively hard, especially when super-durable enemies with powerful hitscan machine guns start to become common, but nonetheless, Descent is a great time.
38. Commander Keen in Goodbye Galaxy! (id Software, 1991)
37. Toonstruck (Burst Studios, 1996)
36. Carmageddon (Stainless Games, 1997)
Max Payne was the game that put Finnish developers Remedy Entertainment on the map. The game at its core is a tale of revenge as a New York cop goes on a killing spree, gunning down the mobsters who killed his family and partner. What made it into something really special, though, was the strong writing in the game thanks to Sam Lake; equal parts disturbing, visceral and funny, Max Payne was an experience unlike any other to that date. Of course, the gameplay also had an innovative element of its own thanks to incorporating "Bullet Time", allowing the player to take on large enemy forces with relative ease by slowing down time in order to effectively dodge enemy fire and draw a bead on them before they could even react.
31. Tetris (Alexei Pajitnov, 1984+)