Number Five, singleplayer

Half-Life

Half-Life is the only game that deserves just as much to be on the multiplayer list as it does on the singleplayer. However, its contributions to singleplayer are far more important, and Half-Life itself is far more accomplished in that area.

Before Half-Life, first-person shooters were simplistic affairs. Levels were created. They were populated with enemies, locked doors, and keys. The player went through, finding the keys and opening the doors. Half-Life totally revamped things. First of all, the story was more than window dressing. While it's an exaggeration to say that Half-Life had a great story, it did have an excellent, consistent setting that it took full advantage of.

The game's creative environments and puzzles, supplemented by some truly trick scripted sequences, made it feel remarkably real. Just think of the anticipation that the non-skippable opening tram ride built up. Before Half-Life, there was almost no such thing as a non-hostile entity in a FPS. Yet, the first level of the game didn't let you shoot anyone, it was only after the accident of the experiment that combat began. Even after that, you'd run into allies here and there who'd help you escape the Black Mesa Facility.

Half-Life is also notable for being the first to truly tackle human beings as a potential enemy AI. Other games had "human" characters, but these were often cartoonized caricatures like ninjas, with little to no AI. Half-Life's AI constructs, particularly the marines, were amazingly lifelike. Marines would spot you, take cover, shoot suppressing fire and throw grenades to flush you out. If you threw a grenade at their position, they'd abandon it like any intelligent being. To this day, there are many games that don't have AI nearly as convincing as Half-Life's. Gamers always judge "human" characters more harshly than they would other entities. For some reason, it makes sense that a monster or blue triangle wouldn't notice if its friends got shot, but a human character can't have even a 5% failure rate without being lambasted for poor AI. Few big games since then have dared to break away from the guidelines sent by Half-Life.

Half-Life's huge installed client base perpetuated what Quake started - online gaming was big. Initially, people were all too happy to play the rather lackadaisical Half-Life deathmatch, but Valve wouldn't sit on its laurels. They acquired the rights to Team Fortress and released Team Fortress Classic as a free download for Half-Life. TF and TFC once seemed to be the ultimate mods, as complicated as we could ever expect from "mere mod teams". Of course, Valve's support was unparalleled and mods took over the gaming scene. Official games like Quake and Tribes were losing their edge compared to free mods like Counter-Strike, which retains its popularity crown after all these years.

For revolutionizing first-person shooter design and helping make realism cool, Valve Software's Half-Life ranks Number Five on FiringSquad's Best Singleplayer Game of All Time list.