HalfLife

A revolutionary FPS about 6 years old (1998) that remains a great game despite its age. The single player game was probably best known for great use of atmosphere, impressive enemy AI (at least for the time), and outstanding level design. As the player, you take on the role of the theoretical physicist GordonFreeman?, working at the sprawling and clandestine Black Mesa research facility in New Mexico. The game has little plot to speak of; it's pretty much like DOOM (interdimensional experiment gone bad lets evil monsters in) but with the whole government cover-up angle. Two add-ons, Blue Shift (meh) and Opposing Force (quite excellent, actually), expanded the single-player experience.

HalfLife's strength and staying power lie in its immersion: although HalfLife is thin on plot, its ambience and atmosphere are unparalleled. In a remarkable design choice that has been successfully duplicated only by the game's sequel (see below), the game takes great pains to avoid breaking your personal connection to Black Mesa. The 18 levels of the original game flow into each other seamlessly, with (but for a few story-related exceptions) no narrative breaks. Furthermore, while the game features a number of friendly characters with whom you can interact, Gordon has no dialogue--HalfLife forces no personality upon you as a protagonist, and GordonFreeman? becomes, in effect, the vessel of your own involvement in its story.

In addition, HalfLife has been popular for it's highly mod-able engine, which has given rise to the most popular multiplayer game of all time (CounterStrike) and the game of choice for weekly CrackInTheAC meetings (NaturalSelection). More recently, HalfLife has been replaced by the long-awaited HalfLifeII, with great graphics, extraordinary physics, and a return to the immersive atmosphere that made its predecessor an instant classic.