X-COM: UFO Defense / UFO: Enemy Unknown / X-COM: Terror from the Deep rookie guide

This is going to be an introduction / rookie guide to one of the best and more addictive DOS games ever made, X-COM: UFO Defense aka UFO: Enemy Unknown.

This game was created in 1994 by Mythos Games, and released around the world by MicroProse, bretter known for their flight simulations. It's a pretty unique game, a mixture of base-building simulation and turn-based strategy with RPG elements.

A better definition could be that UFO is an alien invasion simulator .

Before we start, a couple of warnings.

1) Much of what we are going to cover in this guide also applies to the game's first sequel, X-COM: Terror from the Deep . That's because they are pretty much identical games, although in Terror the alien invasion comes from the seas, which allows for a more sinister atmosphere. Terror also assumes you managed to finish UFO , and it's quite more challenging.

2) Although I first played these games under DOS and I'm an enthusiast of DOSBox (and forks), currently the best way of playing UFO and Terror is through OpenXcom .

OpenXcom is a modern port of the game for Windows, Linux and MacOS. It requieres the original game data, but it offers a more up to date interface, mods, tons of translations ( yes, even to Russian ) and even fixes a few bugs in the original games.

 

The story

I want to keep things brief, so let's say that, congratulations! You're now in complete charge of X-COM , the new international organism created to deal with alien activity on Earth. You'll build and maintain bases, hire personel and investigate alien incidents around the globe. Once a month, the international council will review your results, and decide wether to increase or entirely cut your funding. So yes, keep those countries happy. Intercept UFOs over their territories and keep their cities safe.

Starting out I: Geoscape.



This is the first screen you'll see when starting the game, after deciding the location of your first base. UFO players call it the Geoscape .

The Geoscape is the main interface for the managerial stage of the game. Here we'll get warnings of any alien activity, and using the BASES button we'll manage our base(s).



Here we choose which facilities to build (extra living quarters, laboratory and storage should be your first priority), we equipt our airplanes, manage our storage and hire / sack soldiers, scientists and engineers.

At the start of the game we are given some personel and supplies, but we'll quickly run through them, so we better keep an eye on our weapons and supplies.

The laboratory is especially important for our progress in the game. Here scientists work on whatever assignment we give them, and understanding and then replicating alien technology is the only way to beat the game.



As for our stores and personel, basically we'll hire soldiers, scientists and engineers to replace our ranks or boost our research and fabrication of items.



Also, until we manufacture our own supplies, we must be careful we don't run out of anything.

Eventually, though (and if not use the time buttons to fast-forward), the Geoscape will warn us of an UFO detection. Here's when we use the INTERCEPT option to shoot it down:



Once a UFO has landed or crashed, we can send our manned aircraft SKYRANGER to explore the site, and that's where the ACTION part of the game begins!

--- добавлено 1 ноя 2025, предыдущее сообщение размещено: 1 ноя 2025 ---

Starting out II: Battlescape.



NOTE: At first I'd advise players to avoid combat during nightime. You can tell the time in the crash sites by the "shadow" in the Geoscape. Most of the time, your UFO will be able to wait until morning.

OK, this is the turn-strategy / RPG section of the game. You'll be on the site of the UFO, and to succeed you'll need to eliminate any surviving aliens. If you do, you'll be able to RESEARCH its remains and technology. If you don't... well, Earth will have to learn a new language, and that in the best case scenario.

We move our units one by one, and each has limited time units (the green bar below). Every action (such as walking, firing a weapon or opening a door) will cost you time units. Once you've run out of them, your unit won't be able to move anymore. There are a few other stats, but I won't bother you with them right now.

You'll also notice that there is a "fog of war". That is, the terrain you haven't explored yet is in the dark. You need to explore and clear those areas ASAP.

After moving all your units, click on the round button (top right) . Now it will be the turn of the aliens to move. Their movements will remain hidden unless they happen to be in the line of sight of any of your own units.

Try to keep your units apart, but close enough so they can provide cover to each other.



These buttons are very interesting. If you press them, your units will "save" some time units for actions while in the alien's turn. Basically this means that if an alien happens to cross in front of them, they will shoot them. Depending on the button, this will be an aimed shot, a snap shot or a burst, each with their own success rate and TU consumption.

Eventually, we'll meet our first alien creature:



On our first missions, our only chance will be to dispose of them:



But eventually you'll learn of ways of capturing some of them alive, so we can RESEARCH them.

As for the combat... as I said, move your units carefully. The size and difficulty of each map depends on a series of factors: the size of the UFO, wether it is day or night, the alien species involved, the terrain (urban, country, etc.)... And your men. You're going to lose a lot of them, but as they gain expertise in combat they'll become much, much better. So try to keep them alive.

Anyway, at the end of every combat mission we'll get a brief summary of how well we've done:



Now don't forget to research every creature / item you've recovered!

--- добавлено 1 ноя 2025 ---

Tomorrow I'll see if I can cover some more of the combat phase of the game, but you already got the basics.

Part of the fun in these games is both the surprises and their attention to detail, so I'll try not to ruin the fun for you. Which means, don't expect in-depth explanations, just a quick how-to guide.

 

OK, a few more things about the combat phase of the game.

1) Equipment.

You'll see this screen right before every combat stage. You use it to equip your men with the available items, which are pretty much everything you've loaded into the SKYRANGER.



But you'll also be able to see this screen anytime during the combat, by pressing on the soldier button (top center). By doing this you can reload your weapons, change between them (to equip and use grenades, for instance) and more.

For instance, you'll notice there's a section of the screen which reads GROUND. This means you can throw away unnecessary items (such weapons without ammo) or pick up items from fallen comrades... or aliens, if you have RESEARCHED them previously.

For instance, let's imagine you're in the middle of the mission and your ammo is running low. Not a problem. Stand on the same square as a dead alien and access this screen. If you've researched the weapons it was carrying, you can pick them up and use them!

However, if you haven't researched them, the human will tell you it's an "alien artifact" and won't be able to use it. So keep that in mind. Oh, and naturally, picking up or throwing away items will cost you TIME UNITS.

2) Unmanned units.

As I said earlier, your two priorities in a regular combat mission will be to explore the whole map and eliminate all aliens. Most aliens will be around or inside their UFOs, but you need to explore the whole map anyway because who knows.



This is where unmanned units such as tanks come in handy. A tank has more time units, speed and armament than any of your guys, so they're ideal to explore chunks of terrain. And they're available right from the beginning of the game, in the shape of either cannon or missile tanks.

Disadvantages? Well, if you kill any enemies with your tank, your men won't get any better at their jobs. To improve their abilities you need to use them.

3) Other player stats.

By now you should know how your TIME UNITS work. But what are those other stats for every soldier?



Well, I didn't mention them because they're hardly useful at the beginning of the game. Later on, though, you need to take them into account.

YELLOW means ENERGY. It tells you how tired your soldier is. If you keep moving them or they are overloaded, it can eventually reach zero, in which case the best option is to leave your men to rest during one turn.

RED means HEALTH. At the beginning of the game pretty much every injury is fatal. Later on, as your men become tougher and you learn ways of keeping them protected, a wounded man can still do their job. But unless you heal them, you'll see their HEALTH getting weaker and weaker with every turn, until they collapse or die.

PURPLE means COURAGE or MORALE. Your men are tough cookies, but nobody prepared them for the horrors of alien warfare. So while at first you won't need to pay attention to their mental status, in later stages soldiers can refuse to move, throw away their weapons or go berserk. All these situations can end up with men entering the line of fire of the aliens, becoming completely useless or disappearing in the field of battle.

But don't worry, when that happens the game itself will tell you how to deal with it.