Since they're technically the same game, I've added tips for Enemy Within to our pre-existing guide for Enemy Unknown. All of the Enemy Within tips can be found towards the bottom of each category, and are denoted with a bullet point. You can also check out our Enemy Within review right here.
The X-Com series, particularly the earlier games, are notoriously unforgiving. Although while XCOM: Enemy Unknown has been modernized, and is therefore more player friendly, it’s no slouch either. In fact, even on the Normal difficulty there’s a good chance you’re going to get creamed if you try to breeze through it. But all is not lost. If you find that you’re losing soldiers at an alarming rate or keep getting the project disbanded because a bunch of countries freak out and leave, we've got a few tips you might want to consider.
Facilities are essential. Your manufacturing and research abilities, as well as your satellites, all require the proper facilities to operate. Completing a terror mission to earn five engineers could be a waste if you don’t have enough workshop space to use them. And that could lead to falling perilously behind in the early game arms race.
Research, research, research. Don't neglect your scientists! The technologies they can uncover after studying alien corpses and weaponry are essential to giving your soldiers a fighting chance. By the same token, don't be afraid to take aliens alive. Assuming you can do so with relative safety. It allows you to recover their weapons intact, which can then be equipped on your soldiers or sold for a tidy profit.
Don't ignore the Council. You might prefer to spend your money and resources on better armor and weapons, but if you don't get a few satellites in orbit and ignore the Council's requests you stand to lose immense amounts of funding. Plus you can flat out lose if too many countries abandon the project.
Check your stores often. Sometimes you'll acquire items you don't need for research or manufacturing, and these can be sold off in bulk for a decent price. The same goes for alien tech and specimens you've fully researched. So long as it isn't Ellerium or alien alloys there's a good chance you won't need it for the long haul.
Build smart. Most facilities belong to one of a few different categories, such as energy production or satellite use. Whenever two facilities belonging to the same category are next to each other either horizontally or vertically (i.e. uplink next to an uplink, etc) they both get a bonus. This is a very good thing.
Pay attention to your upgrades. You won’t necessarily have the chance to develop all of them, but many of the projects you can produce at the Forge (once it’s available) can make a huge difference.
Consider holding off on major tasks. Despite all the open-endedness Enemy Unknown’s story does progress linearly. Every so often an urgent mission or task will appear, and once it’s completed the next phase of the story begins. While the alien forces will get more and more difficult to deal with over time, regardless of where you are in the story, there are benefits to keeping the plot in check. Namely it gives you the opportunity to research better equipment and gather more resources before the endgame.
Pay close attention to soldiers' skills. Plan accordingly. Try to select skills that compliment each other, such as the heavy's Holo-Targeting (accuracy bonus to all squad members when firing on an enemy) and the sniper's Squad Sight (can target any enemy that other soldiers see, no matter the distance, so long as there's a clear path to the target).
Consider having two or more of each elite class. It can take some effort but will be worth it. It enables you to create various soldiers with skills that are ideal for a variety of situations; such as a sniper that specializes in large, outdoor environments or an assault soldier ideal for cramped locations.
Upgrade the barracks. Don’t forget about the Officer Training School. Many of the upgrades you can acquire can be a huge help throughout the game; especially the ones that increase the squad size. Check in every so often as more options become available as your soldiers gain higher ranks.
Don't ignore the support class. Having a medic on the team can mean the difference between a favorite soldier spending a few days in the infirmary or getting their own epitaph. Plus their smoke grenades can really help out in a pinch.
Sidearms can be your best friend. Pistols may not seem all that great at first, but they can mean the difference between life and death; especially plasma pistols. Make sure to give your most powerful handguns to your snipers as they can’t move and fire their rifle in the same turn unless they learn a specific perk. Otherwise, if you intend to move them at all, make sure they have rockin’ pistols. And make the effort to manufacture the pistol upgrades when you can, too. I’ve had my snipers take down enemies from quite a distance during their reaction shots using only a pistol on several occasions.
You wanna live? Get a S.H.I.V. The S.H.I.V. is a small robotic vehicle, not unlike a human-sized tank. They’re no replacement for a battle-hardened soldier but with enough research and development they can be quite devastating. Plus they’re the perfect expendable solution to filling an injured soldier’s spot on the squad during a mission.
Use the right armor. You might think it’s clever to put every single soldier in your squad into the most durable armor you can find, but it’s more likely to hinder them. For example, snipers shouldn’t be on the front lines, and therefore could benefit a lot more from armors that may not be super-tough but can help them reach the high ground easier.
Cars can, and will, explode. It seems obvious but I can't stress the importance of keeping an eye out for burning vehicles enough. Cars and trucks do provide decent cover, but once they catch fire it's only a matter of time until they blow. And you don't want your soldiers near them when that happens. So take a moment to see if the vehicle you plan to move to, or are currently hiding behind, is a ticking time bomb before you make a move.
Don't take unnecessary risks. It's often better to miss out on alien tech than to lose a skilled soldier. Take it slow and don't spread out too much. If a soldier encounters an alien squad and no one can reach them within a turn or two, they could be in serious trouble. Splitting up into groups of two or three is usually the best way to go. At least until your soldiers reach the higher ranks.
Head for the high ground. Everyone, soldiers and aliens alike, benefits from a higher elevation. The higher up you are, the better your accuracy and the worse your enemy’s is. It’s not worth taking unnecessary risks to get to the top of a building or anything like that, but if you have the chance to take a higher vantage point then do it.
Never, ever, ever, ever, blindly rush in to a room. It doesn't matter if it's a UFO, base, regular mission, or terror site. It's a sure-fire way to get vaporized. Approach with caution instead. Get at least two soldiers into good positions, preferably with one next to a door or window, and go into Overwatch. Then carefully open the door or peek in on your next turn.
Approach all newly encountered alien species with extreme caution. At least until you know what they're capable of, and especially if you’re new to X-Com. What looks like a pushover could quite possibly decimate your entire squad if given enough of an opportunity. Just assume every new life form you encounter is the most dangerous creature you’re ever going to face and you should be all right.
Take ‘em alive. It’s not always feasible, or worth the risk, but when you can you should try to capture an alien or two alive. Not only can their interrogation lead to new research opportunities, you’ll be able to recover their weapons intact which could save you a fortune in engineering costs.
Push forward at the beginning of your turn, not the end. When you move ahead into unknown territory you always run the risk of encountering a squad of aliens. Believe me, it’s much better to discover them after only moving one or two soldiers than all of them. It leaves the entire squad incredibly vulnerable, especially in the later levels.
Keep Chryssalids as far away as possible at all times. You’ll typically see these spider-like aliens during terror missions but they can (and will) appear elsewhere. KEEP YOUR DISTANCE. Trust me.
Surprise attacks are possible. While the aliens are definitely at an advantage most of the time, they aren’t omnipotent. Use this to lure them into a trap on occasion. If your soldiers can’t see them, they can’t see your soldiers, so it’s possible to set a few up in key locations and use one of your own as a decoy to draw them into range.
Don’t underestimate Sectoids. Sectoids are the most “normal” of Enemy Unknown’s, and possibly the most common. However, while they aren’t particularly durable they can use their telepathic abilities to strengthen their comrades. However, if you kill a Sectoid while its mind is merged with another alien both will die. Keep that in mind.
The Most Important Thing
Be prepared to lose. A lot. Newcomers, especially. XCom is a fair game, but it's also fairly unforgiving. A few wrong decisions early on could create a ripple effect that totally undermines your progress later (see previous tips about selling gear and tending to the Council). Depending on the difficulty and options selected you could also lose a beloved soldier in a flash thanks to one silly mistake. Avoiding these situations is incredibly difficult, but learning from them doesn't have to be.
If you’ve got your own tips and strategies you’d like to recommend feel free to chime in below. With the odds stacked so firmly against us, We'll need whatever help we can get.