The 90’s was a time of PC gaming legends, and few are as fondly remembered or as critically acclaimed as UFO: Enemy Unknown. Later renamed X-COM: UFO Defence for North American audiences, the turn-based strategy cornerstone put you in control of a UN created body tasked with the defence of Earth from a growing extraterrestrial threat.

Taking place in three distinct layers, the first layer is the Geoscape, a very rough representation of the globe. Here the players can place their secret base anywhere they please, from Eastern Europe, to Madagascar, to the icy tundra of Northern Canada. Placing a base is a strategic choice, like most things in UFO, and it made a surprising amount of sense for the technology available to the developers at the time. Antarctica isn’t a high traffic zone for UFO activity, so placing a base up their pretty well ensures your sensors won’t pick up any threats. You also sensed threats on the Geoscape, threats being the little zippy red asterisk of a UFO on the prowl, or the heart stopping green X of a landed craft. It’s funny how even just the small difference between a red asterisk and a green X seemed to convey some sinister intent.

The second layer was base management. Here, the player was greeted by a small resource management game in which they could build facilities, hire personnel, dissect alien corpses, research weapons technology and more. The amount of money available for such things was based on funding provided by X-COM’s sixteen founding nations, doled out through monthly performance reviews. You could research any number of technologies, based on what you thought was important. Medical equipment, weapons, armour, even technology to develop psychic abilities, it was a huge list and it was up to you. It was also the setting for the games only real story progression: alien interrogation. If you captured a live alien and held it in a containment unit, you could have you scientists interrogate the subjects to determine what it was they wanted with Earth.

When a base’s sensors picked up a UFO or terror attack on the Geospace, the player could mobilize fighters to intercept the ship, which was handled through a small mini-game where you could choose cautious, and aggressive attacks, or to keep your distance, in hopes that your fighter could shoot the ship down or force it to land. If successful, players could scramble a troop carrier to the crash site, leading to the third layer: combat, or the Battlescape.

Combat took place on a completely destructible, randomly generated map based on the region, which was a technical feat for the time. You’d drop into farmsteads, residential areas, forest zones, even the desert, and it was different and destructible every time. One of the things that made combat so tense was the mechanic of Time Units. Each soldier (or mechanical weapon platform) on the field had a limited number of time units based on their base statistics, equipment carried, and general health. Every action cost a certain number of Time Units, from movement, to firing a weapon, and even small things like turning, kneeling, or putting an item in your backpack. This turned every movement into a tactical decision, since being carless could leave a soldier standing out in the open, without enough Time Units to even tie their shoes, just begging to catch a hot one from a Sectoid’s plasma rifle. Your view of the battlefield was also based entirely on your unit’s field of view. If they couldn’t see it, neither could you. Conversely, just because you couldn’t see the aliens, doesn’t mean that they couldn’t see your soldiers. This lead to horribly stressful situations like lethal plasma shots ringing out from darkened windows, or missing a shot and having your target escape into the darkness only to have them sneak up behind you the next turn. This, combined with the importance of Time Units, forced you to move soldiers like a SWAT team, from cover to cover, trying to keep all means of entry in your field of view.

Another thing about UFO that may throw a lot of modern gamers is the complete lack of direction and handholding. From the get-go, the game threw you to the wolves. There was no plot upfront except “OH GOD! ALIENS!”, and it was left up to the player to discover what it was they were supposed to do through interrogation of live alien captives. You could even fill in the world’s back story through dissecting alien corpses, seeing what made them tick, with a surprising amount of detail for such a hidden part of the game. Or you didn’t. The choice was completely up to you! Even on Beginner difficulty, it could be a merciless game, but that’s part of what made it so exciting. Soldiers were so fragile that, even in later parts of the game, people you’ve come to rely on for the majority of your missions could be shot down the very next turn, without warning.

The game isn’t without its dated portions. The base, with its pastel grid patterns, had the look of a deserted office building rather than a secret government base. The soldiers, while showing slight variation in the squad load-out screen, all became identical blonde men and women in Top Gun jump suits once boots hit dirt on the Battlescape. The controls were… less than ideal. In fact, it could be a downright nightmare just to throw a grenade, but it was all to give you the maximum amount of control possible over a situation.

Make no mistake: UFO is an old game, but it’s an awesome one. It was received well when it came out, and spawned numerous inferior sequels, but it has since become considered one of the greatest games ever made. It’s won hundreds of “Greatest Made” awards, and was inducted into more than one Hall of Fame. It’s not hard to see why. It created, and defined a genre no one else has gotten quite right since, which isn’t to say no one is trying. Indie team Goldhawk Interactive are working on a spiritual remake called Xenonauts, and Firaxis Games recently announced a full on 3D cross-platform remake called XCOM: Enemy Unknown. Both are different, both are exciting, and we’ll see if either can hold up to the majesty of the original.