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Impossible Difficulty Strategy Guide

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This guide is on strategy for playing XCOM: Enemy Unknown on Impossible difficulty. For advice on tactical combat, see the Impossible Difficulty Combat Guide article.
Impossible

General information and advice Edit

Premise Edit

Beating the game on Impossible is very possible. The main struggle will come in the first few months of the game, and after you get everything going, it's a walk in the park.

To begin with, there is no tutorial for Impossible, and the game begins with the Starter Mission.

Before you start check out the major changes on Impossible difficulty.

Picking a start continent Edit

EuropeEdit

Halves the construction price and maintenance upkeep of Workshops and Laboratories.

  • Savings of §65 for each Workshop and Laboratory.
  • Contains four countries
    • Highest gross monthly income of any continent.
    • Can sacrifice three countries on Abduction Missions and other countries can be saved.
  • Recommended for experienced players; the high savings makes building large quantities of Workshops and Laboratories in the early months easier.
  • Not recommended as start continent; other continents are far better.

South AmericaEdit

Instant interrogations and autopsies; Halves subsequent research times.

  • Savings of 3-5 research days for each interrogations and autopsy.
  • Contains two countries:
    • Lowest gross monthly income of any continent.
    • Fastest satellite coverage (need only 2).
  • Enemy Unknown
    • Viable -only if- an Alien Containment is constructed.
    • Not recommended as start continent; other continents are far better.
  • Enemy Within
    • Vital point targeting and instant autopsies will make this a powerful starting place if Mecs a favored unit. 
    • An Alien Containment is not relevant, but helpful (interrogations are also instant), rushing squad size is a better option.  2 Mecs and a support with 3 smoke grenades is very help, a heavy for the shield as mec is also quite good.  Thin men's crit are what wreck mecs.

North AmericaEdit

Halves the construction price and maintenance upkeep of Satellites, Interceptors, and Firestorms.

  • Drops the price of Interceptors from §40 to §20, and their maintenance from §20 to §10.
  • Contains three countries:
    • The United States grants §180, the largest starting cash of any continent.
  • Recommended as start continent for beginners; the moderate savings makes building and protecting satellites in the early months easier.

AfricaEdit

Increases XCOM total gross monthly income by 30%.

  • Monthly income increases exponentially as more countries are covered with satellites.
  • Contains three countries:
    • At the start, gives §210 (instead of §165),
    • Second highest gross monthly income of any continent.
  • Recommended for experienced players; if willing to sacrifice other savings and bonuses for early cash.
  • Recommended as start continent; it effectively grants more money than the United States in the early months.

AsiaEdit

Halves the credit cost of all Foundry projects and Officer training.

  • Savings of §65 for each project
  • Contains four countries
    • Average gross monthly income of any continent.
    • Can sacrifice three countries on Abduction Missions and other countries can be saved.
  • Recommended as start continent; grants early access to Ammo Conservation, Tactical Rigging, Squad Size II, and Lead By Example.

Tactical Advice (for Impossible Ironman)Edit

  • During missions, time is on your side, go slow. If a situation looks impossible, don't advance into it. Wait it out, they'll come to you, eventually. (If there is a bomb going off, this isn't quite as true, but you do have time there too.)
  • Enemy within: Don't worry about that Meld.  It's the bait to make you rush the map, but it's not worth that much.
  • Use explosives liberally, especially to destroy cover. (Dr. Valen's warning is... terrible at best.) You should be able to hit 2 aliens per grenade/rocket use (though grenading heavy cover can be more important). 3+ should be achievable with rockets. Rocketing vehicles' engines explodes them immediately.
  • Exposed aliens when Overwatched are "bugged":
    • They usually do nothing (but if they have a shot with high aim value because your troopers are also exposed or staying too close, they will still take the shot instead of doing nothing.) This is very useful to kill/capture aliens.  Note that ANY trooper can over watch them, the ones that are exposed can shoot them.
    • IMPORTANT: This tactic does not work in Enemy Within; the "bug" in the AI that was "fixed" in the expansion.)
  • If your squad dies on the 1st mission the game will restart that mission for you. 1st mission every soldier with a kill is promoted.
  • You will probably have to bring in recruits at bad times, give them Chitin Plating if they aren't Snipers with Squadsight.

Sniper ClassEdit

Top priority should be getting 2 snipers with Squadsight. Once you get that, it's easier. Once they get 'fricking lazors strapped to their fore heads', it's a lot easier. Get one Double Tap and get one In the Zone. This is Iron Man right? So when those six heavy floaters jump you while you are fighting the Muton Elites, you aren't reloading a game. Explosives and In The Zone should end them (bonus, you can reload on that turn). Look behind you, etc, there is usually some high ground (out of sight some times). Use Battle Scanners to scout for rockets.

Support ClassEdit

Second priority should be getting 2 Supports leveled. Healing and suppressing fire make the game a lot easier. Increased movement to run in for the stun is also great (sadly you cannot run and gun an Arc Thrower).

Heavy ClassEdit

Third priority should be getting 2 Heavies leveled. You will have 4-6 rockets , you will own city missions (abductions/terror) with 2 heavies.  Get Shredder Rocket, and double rockets. Destroy cover and soften up targets for In the Zone. Between a Heavy and In the Zone, 3+ kills per turn with the 2 of them is very reasonable.

Assault ClassEdit

Last priority should be getting 2 Assaults leveled. Use assault rifles, not shotguns (alloy cannons, though, are good). Rapid Fire and Flush are both great (there is no cooldown on Rapid Fire). The survival skills are much better than the crit skills (that plus stims and you are well nigh unkillable). Assaults are expendable, plan on losing them(they are a hell of a lot better to lose than anything else).

MEC Trooper ClassEdit

On impossible ironman the usefulness of an early game MEC is debatable. Endgame it's a good idea to convert one or both of your snipers if they don't get psionics. This effectively gives them higher damage and removes the cooldown on double tap at the expense of sqaudsight.

Step by Step Walkthrough Edit

First month Edit

Main article: Impossible Difficulty Combat Guide

The first month is the most difficult (and critical) section of the game on Impossible difficulty. Sectoids are stronger and always outnumbered Xcom soldiers. Thin Men requires more luck than skill.

  1. Top priority is to win combat missions without losing soldiers. In first month always use the best soldiers if possible, try to kill at least one enemy with every soldier, so they can level up faster, especially Snipers. Leverage your knowledge of map terrain for better ambush positions. Know thy enemy, their numbers, their stats and weaknesses. Chivalry is death, so always fight dirty.
  2. Second priority is base management and research, plan forward to maximize satellite coverage. The difference between 100% world cover and 7 succeeding Council nations is largely dictated within the first two months.

Major events Edit

There will be 6 major events during the month.

  • First Mission (Fixed event)
  • First Abduction Mission (Fixed event)
  • First UFO Contact (Fixed event)
  • Second Abduction Mission
  • Council mission (Thin Men appear)
  • Council Report

Enemy types and numbersEdit

  • First Mission: 8 Sectoids (two groups of 3 and one group of 2)
  • Abduction Mission: Either 12 Sectoids (four groups of 3), or 10 Sectoids (two 3s and two 2s), depending on the description of mission difficulty.
  • First UFO Contact: 4 Sectoids (two groups of 2) and 1 Outsider (inside UFO).
  • Council Mission:
    • Target Escort/Extraction: 6-7 Sectoids (two groups of 3, or one group of 3 and a pair of 2s) and 5 Thin Men (one can be found around the map, mostly at the center, others will spawn as soldiers move forward with the allied civilian).
    • Bomb Disposal: 6 Sectoids (two groups of 3) and 5 Thin Men (one can be found around the map, mostly at the center, four will spawn when you defuse the bomb).
  • Slingshot Mission Friends In Low Places: 6 Thin Men on Overwatch, 3 Sectoids (1 group of 2, and 1 alone), 1 high level alien (Muton or Chryssalid)

First month strategy Edit

Strategy Number One Edit

  • After completing the First Mission:
  1. Build your first satellite
  2. Research Weapon Fragments (it takes 8 day to research)
  3. Excavate the entire first floor
  4. Scan the planet
  • When first Abduction Mission appears, go for a mission with 4 Engineers reward. (At the end of the month, 10 engineers are required to build Satellite Uplink, 6 Engineers to build a Workshop and 12 to build Laser Rifles and Laser Pistols.)
  • After completing Abduction Mission build a satellite (it costs only §77 now), then Scan.
  • If Weapon Fragments research completed before first UFO contact, start Alien Materials, then Scan.
  • Shoot down your first UFO and complete the ground mission.
  • After first UFO contact Beam Weapons is available if Weapons Fragments research is completed. Start Beam Weapons or switch to it, even if only a few days left in Alien Materials.
    • Beam weapons takes 24 days (41 days on Enemy Within) with 5 Scientists, so it will be finished right after the end of the first month. 
    • To reduce research time, obtain 4 scientists as a reward on the second Abduction Mission.  A seargent is the only possible better reward (if you don't have one).
    • 12 Engineers are required to build these weapon (build a Workshop if necessary)
    • Without Laser Rifle and Laser Pistol, the second month is needlessly difficult.
      • Scan the planet.
  • The next two missions can be an Abduction Mission or a Council mission.
  • If the Council Mission appears before second Abduction Mission, with some luck you can get 4 Engineers, 4 Scientists or a panic reduction on an important country. Choosing rewards on second Abduction Mission can depend on this.
  • When the second Abduction Mission appears, choose 4 Engineers as reward if possible. If not, then choose 4 Scientists or try to save Africa.
  • Before Council Report launch your satellite on a country with 5 panic level, first priority is Africa, then the country with highest income. Move one of your Interceptors to the new continent. Scan to next month.
  • Slingshot Content Pack: if you own the Slingshot DLC pack, you must make an extra decision on the first month. Upon receiving the council mission, you will get to choose from random council missions or the Slingshot mission pack. If you decide to choose the Slingshot mission pack, you can complete all 3 of them during the first 2 months of the game. Friends In Low Places is the first mission which involves escorting a VIP to the extraction zone. You will face a total of 6 Thin Men, 3 Sectoids and a random high level alien: a Muton or a Chryssalid. This is a rather challenging mission which will involve probably the loss of 1 soldier to the last high level alien. The rewards are §200, 2 Scientists and 2 Engineers, as well as Shaojie Zhang, a lieutenant Heavy with 9 base HP.

Strategy Number Two Edit

  • Objective: survive the invasion.

Be prepared: you are likely going to lose 4 countries in the first month but with good game play it is possible to lose only one of them. One of the ways to keep a Country is to "fish" for Council Missions in that Country with panic reduction reward. To do that, reload a save made at any time before the mission was announced. Council mission is random every time, and reward is random every time. The countries you should lose better be at your starting continent. This way, you won't lose the possibility to acquire all continent bonuses.

There are two general approaches to development in the first month.

First way is to focus on Satellites and base facilities to lay the monetary foundation for future months. It will require a lot of skill with handling your soldiers to avoid losses, but it will keep more countries from leaving the Council, due to launching more satellites. To help yourself with ground missions, it's a good call to research armor, for more HP. If you feel really confident, research the Arc Thrower and keep capturing aliens, to reduce research times and enable Alien Base Assault sooner.

It is possible not to lose any countries at all. Calendar of key events should be the following:

  • If you need to, you can excavate and still have time to build a Workshop on the site immediately afterwards (care is required: completion of excavation does not stop the Geoscape scan, so you need to ensure that you stop the scan as soon as the excavation is complete in order to build a workshop (see below).
  • 2-7 March. Go for a Mission with 4 Engineers reward. (You need 10 engineers to build Satellite Uplink and you will need 6 Engineers to build a Workshop.)
  • 2-7 March. Build a Workshop (completed March 17th)
  • 11 March. Now prices drop and you can buy 4 Satellites §77 each if possible (It is not always possible to buy as many as 4; further, you are not guaranteed another mission between 11th March and 17th, so it is risky to spend all of your money on the 10th (unless you can only afford a single satellite) without leaving enough for a Satellite Uplink).
  • 17 March. Build Satellite Uplink (completed March 31st)
  • 31 March. Launch your satellites (while the protection from abductions the Satellites provide wont be active yet at the council meeting the next day, the panic reduction and income are instantaneously awarded and those are all you need to prevent the countries from leaving the council)

Some tips how obtain enough Credits:

  • Sell some items on the Gray Market
  • Skip first Small UFO. You will get a Medium UFO
  • Don't buy Interceptors before 27 March. You will not detect a second UFO in March

Second way is to focus on making ground missions easier. While more reliable for ground missions, this is less monetarily rewarding, and will likely result in more countries leaving The Council, due to fewer satellites.

  • Start in North America. It gives the most $ in the 1st 2 months if you buy interceptors. And you should have 3 on your first 2 continents so that you definitely shoot down the medium UFO month two. That means North America yields $100 in the first 32(i.e. the start of month 2) days due to interceptors, and the extra $160 you get from the fact that America is $180 and not $100(compared to say China).
  • Start excavations of level 1 immediately. You are going to fill it.
  • Pick your first mission reward as Scientists. After that you'll probably need all engineers to keep up with your advances. At the end of month one you should have an Officer Training School and Alien Containment.
  • If you got scientists as your first reward you should be able to capture a Sectoid month one. Count groups, know your maps (some maps have group off by themselves that don't move). Get that Sectoid for the beam weapons credit. [If you do this you should have all beam weapons completely finished by month 2. The game is now a cakewalk (you got all the UFOs down for the alloy right?). That's right, it's the Impossible Ironman cake walk. I tired all those guides about "Engineers!", yeah 1st time doing this was easy.]
  • On the second abduction mission, select 4 Engineers as a reward.
  • Build a Power Generator, Alien Containment, Officer Training School and Elevator when you can (you need a generator to build all this).
  • At the Council meeting, it is likely that three countries will abandon the project. Choosing which country to give satellite coverage:
  • You already got the bonus of your starting continent so these countries can be sacrificed. Asia and Europe have the most 'sacrificial' countries.
  • Pick a country based on immediate cash, Russia is best, most $. Though pick a country that will defect otherwise.

Second month Edit

With Laser Weapons, this month could be easier than the first. At the start you need at least 2 Laser Rifles (one for Assault, one for Support) and one Laser Pistol for SniperThin Men and Chryssalids are the greatest threat, focus on them. If you survive Alien Terror Attack, the rest of the month should not be a problem. Top priority is to save Africa, build a Satellite Uplink, 3 Satellites, research Laser Weapons, Carapace Armor and Experimental Warfare.

Major eventsEdit

These events occur randomly.

  • Floaters will appear on ground missions, equipped with Light Plasma Rifle (Fixed event)
  • Two Abduction Missions
  • Two UFO Landing Site / UFO Contact
  • Alien Terror Attack (Chryssalids will appear in this mission, fixed event)
  • Council Report

Enemy types and numbersEdit

  • Abduction Mission:  Combination 1: 3 Floaters, 6 Sectoids (two groups of 3) and 3 Thin Men.  Combination 2: 9 Sectoids, and 3 Floaters.  Combination 3: 9 Floaters and 3 Sectoids.
  • UFO Contact/UFO Landing Site:
    • Small UFO (+1 in each group if landed): Combination 1: 2 Floaters, 2 Sectoids and 1 Outsider.  Combination 2: 4 Floaters and 1 Outsiders.  Combination 3: 2 Floaters, 2 Thin Men and 1 Outsider.
    • Medium UFO (+1 in each group if landed): Combination 1: 2 Floaters, 2 Sectoids, 2 Thin Men and 1 Outsider.  Combination 2: 5 Floaters (two groups), 2 Sectoids, and 1 Outsider.  Combination 3: 2 Sectoids, 4 Thin men and 1 Outsider.
  • Alien Terror Attack: Combination 1: 6 Floaters (two groups of 3) and 3 Chryssalids (they will attack civilians even in fog of war, expect heavy Zombie overrush or more Chryssalids).

Second month strategyEdit

Strategy Number OneEdit

  • At the start of the second month build a Satellite Uplink and 3 satellites (Satellite Uplinks should be grouped together to get adjacency bonus). Sell some items on the Gray Market if you don't have enough money. Finish Beam Weapons and start Alien Materials (it takes 8 days with 5 Scientists). If you were lucky and got extra Scientists during the first month and already finished Beam Weapons and Alien Materials research, start Carapace Armor (it takes 28 day with 5 Scientists). You can survive the second month without Carapace Armor but it is recommended for the third month. If you are able to finish Carapace Armor research this month, start Experimental Warfare. Scan the planet.
  • If an Abduction Mission appears, choose the reward which is most beneficial. At the end of the month you need at least 20 Engineers to build your next Satellite Uplink. Complete the mission and Scan.
  • When first UFO Landing Site / UFO Contact appears: after completing the ground mission sell some items on the Gray Market, mainly damaged items. Build an Access Lift (§50 and 2 Power) and at least one Power Generator (§60). Build a second Power Generator if you can afford it.
  • Alien Terror Attack is a really difficult mission this month. Build enough Laser Rifles and Laser Pistols for your soldiers.
  • When a second UFO Landing Site / UFO Contact appears: after completing the ground mission sell some items on the Gray Market, mainly damaged items. Build a second Power Generator and/or an Officer Training School and/or a Workshops if you have some spare money.
  • Before Council Report launch your satellite on a country with 5 panic level; first priority is Africa then the country with highest income. If there is a new continent with a satellite build Interceptors and move one there. Scan to next month.
  • Slingshot Content Pack: If during the first month you chose to play the Slingshot DLC council missions, in this month you can complete Confounding Light and Gangplank both in a short timeframe, or you can ignore the council request until you are prepared. Note that if you ignore the council request for these 2 missions, future council requests will be the same 2 missions, until you complete them. If you decide to tackle these missions now, you will receive as rewards 2 scientists, 2 engineers, and the loot from the alien battleship, including high amounts of Elerium, Alien Alloys as well as 2 Fusion Core and the research projects for the Blaster Launcher and the Fusion Lance
    • Confounding Light: it's best to rush the mission as it has a turn limit that is not extended by completing the objectives. You will face 4 squads of 2 Thin Men, as well as 2 Mutons that will be transported into Overwatch when you successfully activate a transponder. Ignore all aliens except the ones inside the train. Use of Support class with the Sprinter ability is highly recommended, and keep 1 rocket from a Heavy to clear the driving room, which will have two unflankable holed up Thin Men in it. You will lose soldiers in this mission, so be prepared.
    • Gangplank: This mission is extremely challenging early on, as the amount and diversity of enemies makes short work of your unprepared squad, it is recommended to have at least Laser Rifles and Carapace Armor for this mission. Creep-walking (advancing slowly in Overwatch) is heavily recommended, and retreating often and baiting enemies into your comfort zone is the only way to actually advance in the mission. Supports with Revive are a must have in this mission.

Strategy Number TwoEdit

  • Objective: preparation for raiding the Alien Base, and the actual raid if possible.
  • Sell alien autopsy parts and UFO parts for cash.  (You only might want to keep Floaters, the rest, you should have the tech to kill them without the boosts.)
  • Build out lasers for all of your soldiers.
  • Laser Rifles > Laser Sniper Rifles > Heavy Lasers > Interceptor Lasers.  Give snipers laser pistols.  Laser pistols and Gunslinger will turn snipers into a regular Doc Holiday.  In the Zone only works once per turn with a pistol.
  • Leave normal pistols on the Assault/Support to do precision work for captures.
  • Start armor once you have lasers done.  Capturing a floater gives basic armor credit(and those guys like to close, so that should be pretty easy).

Raiding the Alien Base is beneficial. Successfully completing the mission will reduce panic by 2 points worldwide, allowing you to prevent any countries from leaving the Council in this month. It's best to complete the mission shortly before the Council report. Additionally, it will provide you with a lot of § , and gives you a chance to research Psi-Abilities for your soldiers.

Base managementEdit

  • Build a Thermo Generator (§200) if you have easy access to a steam vent and it's reasonably close by.
  • Satellite Uplinks grouped together get adjacency bonus. Four uplinks built in a square will cover 12 satellites (8 from satellites + 4 from adjacent bonus = 12). Construction should begin no later than 15 days before the Council report.
  • Engineer requirement for uplinks increases with every uplink you build, so you have to increase the number of Engineers you have. This can be done by choosing Engineers as a reward for missions and by building Workshops. A Workshop takes 10 day to build, so you need to start construction at least 25 days before the Council report.
  • To enable Alien Base Assault, you require an Alien Containment facility (§85), and it takes a week to build, so start building early. After constructing it, you will need to successfully capture any alien and interrogate it. Next step is to capture an Outsider on a ground UFO mission, then research the Outsider Shard.

Third month Edit

With Laser Weapons and Carapace Armor, you have a quite good chance to survive this month, however you still need to use your best tactics on ground missions. Top priority is to save Africa, build a Satellite Uplink, 3 Satellites, an Officer Training SchoolPhoenix Cannon for your Interceptors, research Autopsies, Skeleton SuitPrecision Lasers and Heavy Lasers if possible.

Major eventsEdit

These events occur randomly.

  • Mutons will appear on ground missions, equipped with Light Plasma Rifles and Alien Grenades (Fixed event)
  • Two UFO Contact/ UFO Landing (first UFO Contact is an Abductor, fixed event)
  • Two Abduction Mission
  • Council Mission
  • Council Report

Enemy types and numbersEdit

Types and numbers may change randomly. These are mostly possibilities.

  • UFO Contact/ UFO Landing:
    • ​Abductor UFO:
    • Large Scout: Combination 1: 3 Floaters, 6 Sectoids (two groups of 3) and 1 Outsider.  Combination 2: 6 Floaters, 3 Thin Men, 3 Mutons, and 1 Outsider.  Combination 3: 6 Mutons, 3 Floaters and 1 Outsiders.
  • Abduction Mission:
    • First Abduction Mission: Combination 1: 5 Floaters (one group of 3 and one group of 2) and 3 Sectoids.  Combination 2: 6 Sectoids and 2 Thin Men.
    • Second Abduction Mission: Combination 1: 6 Floaters (two groups of 3) and 6 Thin Men (two groups of 3).  Combination 2: 6 Mutons, 3 Floaters and 3 Sectoids. 
  • Council Mission:
    • Target Escort/Extraction: 16 Thin Men (two groups of 3, two groups of 2, others will spawn as you move forward with your allied civilian)

Third month strategyEdit

Strategy Number OneEdit

  • At the start of the third month build a Satellite Uplink and 3 satellites (Satellite Uplinks should be grouped together to get adjacency bonus). Sell some items on the Gray Market if you don't have enough money. Excavate second floor. Build an Officer Training School if you haven't done so yet, then increase the size of your squad. Research Experimental Warfare, when finished, build Phoenix Cannon for your Interceptors. After Experimental Warfare, choose a research which is most beneficial. You have enough Scientists by now to finish Xeno-Biology within a few days, then Autopsies (Floater Autopsy is recommended).
  • UFO Landing Site / UFO Contact appear. First time it will be an Abductor UFO. Without Phoenix Cannon it is almost impossible to shoot it down, with Defense Matrix (Dodge) and Uplink Targeting (Aim) you might have a little chance. Don't lose your Interceptor, if an Abductor UFO escapes, nothing will happen, however you will miss a chance to collect a nice amount of materials.
  • When an Abduction Mission appears, choose a reward which is most beneficial. At the end of the month you need at least 30 Engineers to build your next Satellite Uplink. Build a Workshop and Power Generator if necessary.
  • When a Council Mission appears, enemies will be only Thin Men. With 6 soldiers, equipped with Carapace Armor and Laser Weapons, this mission shouldn't be a problem. Recommended to bring Support with Medikit and Field Medic ability, so you don't have to worry about poison. Bring one or two Rookie or Squaddie, so they can get some XP and even Level Up.
  • UFO Landing Site / UFO Contact appear. It will be a Large Scout. Without Phoenix Cannon it is almost impossible to shoot it down, with Defense Matrix and Uplink Targeting, you might have a chance. Don`t lose your Interceptor. If a Large Scout escapes, panic will rise in that country.
  • Before Council Report launch your satellite on a country with 5 panic level, first priority is Africa then the country with highest income. If there is a new continent with satellite, build an Interceptor and move one there. Scan to next month.

Strategy Number TwoEdit

To successfully complete the priority mission, you have to interrogate any captured alien, then stun an Outsider, research the Outsider Shard it leaves behind, and manufacture a Skeleton Key. By this time, XCOM finances should be stable enough to allow you to launch the remaining satellites without more countries leaving the Council. Manage your base, build the necessary facilities, and lay off satellites until the end of the month. When the Council report draws close, make sure your best men are healed up, and go for the Base.

Enemy forces inside the base will typically consist of one Sectoid Commander, two groups of two Drones (four in total), one or several groups of Mutons, several groups of Chryssalids, one or several groups of Floaters, and one or several groups of Thin Men or Sectoids. Most aliens are grouped by three, with the exception of Drones.

Further development Edit

After raiding the Alien Base you should be very well set off. Just cover the rest of the countries with satellites, finish all weapon and armor research, max out your soldiers' ranks, and avoid losses. Once you stabilize the situation and gear well enough, you should be in no danger of losing the game by having more countries withdraw from the Council. From this point, you can take the game slowly, and complete all the researches before taking on further priority missions.

Note that in Enemy Within, raiding the Alien Base triggers the countdown until the alien counter-attack on XCOM headquarters. This is an extremely difficult mission early on, especially with the inability to pick your squad resulting in a chance for you to be facing enemies such as Cyberdiscs and Mechtoids with nothing but rookies.

Fourth monthEdit

Probably this will be the last month you need to a build Satellite Uplink and Satellites to cover all the remaining countries. If you managed to research Skeleton SuitPrecision Lasers and Heavy Lasers, build and equip your soldiers with these items. The Skeleton Suit gives you only +3 HP (Carapace Armor gives +4), however for sacrificing that one extra HP, you gain +10 Defense (that's 50 Defense behind full cover), extra movement (Basic = 14 square +1 if dashing; Skeleton Suit = 18 square +1 if dashing; which is recommended for flanking) and Grappling Hook (useful for Snipers mostly). Top priority is to save remaining countries, build a Satellite Uplink, 4 Satellite, choose a research which mostly beneficial, try to capture and interrogate aliens.

Major eventsEdit

These events are occurring randomly.

  • Cyberdisc and Drones will appear on ground missions, Mutons will be equipped with Plasma Rifle (Fix event)
  • Two UFO Contact/ UFO Landing
  • Abduction Mission (if there is any country left without Satellite)
  • Alien Terror Attack
  • Council Report

Enemy types and numbersEdit

Types and numbers may change randomly. These are mostly possibilities.

  • UFO Contact/ UFO Landing:
    • ​Small Scout: 1 Cyberdisc with 2 Drones, 3 Thin Men, 3 Muton and 1 Outsider
    • Large Scout: Combination 1: 6 Muton, 6 Sectoid and 1 Outsider.  Combination 2: 2 Mutons, 2 Cyberdiscs with 3 Drones (in 2 groups), 2 Floaters, and 1 Outsider.
  • ​Abduction Mission: 5 Floater, 1 Cyberdisc and 2 Drone.  Combination 2: 1 Cyberdisc with 2 Drones, 2 Mutons, 3 Thin Men, and 2 Sectoids.
  • Alien Terror Attack: 6 Chryssalid, 1 Cyberdisc, 2 Drone and 3 Floater.  Combination 2: 9 Chryssalids, 1 Cyberdisc with 2 Drones, 3 Floaters.

​Fourth month strategyEdit

Strategy Number OneEdit

  • At the start of the fourth month build a Satellite Uplink and 4 satellites (depends on remaining countries). Sell some items on the Gray Market if you don't have enough money. Excavate second floor, build an Access Lift, a Power Generator (if necessary) and Alien Containment facility.
  • On ground missions, try to capture at least one alien (Sectoid unlocks Plasma Pistol; Thin Men, Floater and Outsider unlocks Light Plasma Rifle; Muton unlocks Plasma Rifle). Bringing at least one or two Heavy is highly recommended.
  • Before Council Report launch your satellites on remaining countries. If there is a new continent with satellite, build an Interceptors and move one there. Scan to next month.

Fifth monthEdit

By now you may have all the remaining countries covered with Satellites (or build one more Satellite Uplink if necessary, but for saving only one country it isn't recommended). From now on take your time, research everything you need, capture aliens, salvage weapons, level up your soldiers, purchase upgrades in the Foundry and Officer Training School or proceed with the main story. If you managed to research and build enough Titan Armor and Plasma Weapons for your squad before the end of the month, it is worth considering to assault the Alien Base before stronger enemies (such as SectopodsMuton Elites and Heavy Floaters) appear.

Major eventsEdit

These events are occurring randomly.

  • Berserker will appear on ground missions (Fix event)
  • Two UFO Contact/Landing
  • Council Mission

Enemy types and numbersEdit

Types and numbers may change randomly. These are mostly possibilities.


  • Abduction Mission: 3 Berserker with 4 Mutons (in 3 groups), and 1 Cyberdisc with 2 Drones.
  • UFO Contact/Landing:
    • Supply Barge: 2 Berserkers with 4 Mutons (in 2 groups), 3 Mutons, 1 Cyberdisc with 2 Drones, and 3 Sectoid Commanders.
    • Large Scout: 1 Berserker with 2 Muton, 3 Muton, 1 Cyberdisc with 2 Drones and 1 Outsider.  Combination 2: 1 Berserker with 1 Muton, 2 Mutons, and 1 Outsider.(Crashing)
    • Abductor: 2 Berserker with 2-2 Muton, 3 Muton, 1 Cyberdisc with 2 Drones and 2 Outsider
  • Council Mission:
    • Bomb Disposal: 18 Thin Men (four groups of 3, six will spawn when the bomb is defused)
  • Alien Base: 2 Cyberdisc with 3 Drones (in 2 groups), 4 Drones without Cyberdisc (in 2 groups), 3 Mutons, 3 Thin Men, 3 Chryssalids, 3 Floaters, 2 Berserker with 4 Muton (in 2 groups), 1 Sectoid Commander.   

Sixth monthEdit

By now you should have Titan Armor and Plasma Weapons for your squad. It is worth considering to assault the Alien Base before stronger enemies (such as Sectopods and Muton Elites) appear.

Major eventsEdit

These events are occurring randomly.

  • Heavy Floater will appear on ground missions (Fix event)
  • Two UFO Contact/Landing
  • Alien Terror Attack
  • Council Report

Enemy types and numbersEdit

Types and numbers may change randomly. These are mostly possibilities.

  • UFO Contact/Landing:
    • Supply Barge (Crashed): 8 Heavy Floaters, 1 Cyberdisc with 2 Drones and 1 Outsider or Sectoid Commander 
    • Small Scout (Crashed): 2 Heavy Floaters, 1 Berserker with 1 Muton and 1 Outsider or Sectoid Commander
  • Alien Terror Attack: 3 Floaters, 6 Heavy Floaters, 1 Berserker with 2 Mutons and 1 Cyberdisc with 2 Drones
  • Alien Base: 6 Heavy Floaters, 4 Drones, 4 Berserker, 14 Mutons and 1 Sectoid Commander

​Seventh monthEdit

If you managed to research and build Ghost Armor and Firestorm, try to shoot down a Battleship. Battleship will appear if you leave a Scout UFO to escape without engaging with it.

Major eventsEdit

These events are occurring randomly.

  • Muton Elite and Sectopod will appear on ground missions (Fix event)
  • Two UFO Contact/Landing
  • Council Mission

​Enemy types and numbersEdit

Types and numbers may change randomly. These are mostly possibilities.

  • UFO Contact/Landing:
    • Large Scout (Landed): 3 Mutons, 6 Muton Elite, 1 Cyberdisc with 2 Drones and 2 Sectoid Commander or Outsider
    • Supply Barge (Landed): 6 Muton Elite, 3 Berserker with 6 Mutons, 1 Cyberdisc with 2 Drones, 1 Sectopod with 2 Drones and 2 Sectoid Commanders
  • Council Mission:
    • Assets Recovery: 12 Sectoid

Eighth monthEdit

By now you should have Ghost Armor for your squad and Firestorm in each continent, shoot down and raid a Battleship if you haven't done yet. After researching and building the Blaster Launcher you have everything you need to follow the main story and finish the game.

Major eventsEdit

These events are occurring randomly.

Enemy types and numbersEdit

Types and numbers may change randomly. These are mostly possibilities.

  • UFO Contact/Landing:
    • Large Scout (Crashed): 2 Muton Elite, 2 Muton, 1 Cyberdisc with 1 Drone and 2 Sectoid Commander
    • Battleship:
    • Overseer: 6 Muton Elite (two group of 3), 2 Sectopod with 4 Drones and 1 Ethereal with 2 Muton Elite
  • Council Mission:
    • Bomb Disposal: 18 Thin Men (four group of 3, six will spawn when the bomb is defused)
  • Alien Terror Attack: 6 Heavy Floater, 1 Cyberdisc with 2 Drones, 1 Sectopod with 2 Drones and 3 Chryssalids

See AlsoEdit

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