X-COM 2 Strategy: 50 Best Tips to Beat Legend Ironman

Updated:

23 Aug 2024

Legend Ironman. Only The Strongest Xcom Players Will Survive

Are you tired of getting ass-kicked in Legend Ironman mode? Here are the best Xcom 2 tips to make you Earth's hero and stop the AVATAR project in its tracks.
Good luck, commander.

AVATAR Project:

There are a total of 12 bars in the Avatar Project. Once it fills up, the doom timer starts.

First off, let's clear up the air on a few misconceptions and how to effectively beat it without the risk of defeat early on.

When all the Avatar Project red bars fill up, it starts a “Doom Timer” and at this point you have between 26-28 days on Legendary to prevent an Alien victory. This has been changed on Alien Hunter DLC. The Doom Timer resets to 4-7 days instead of 26-28 days (on the 2nd trigger).
To remove the timer, you must destroy an alien facility or complete one of the story missions.
Starting mid game, you should have at least one alien facility or black site mission accessible. The timer can be waited down to 1-7 days - depending on how skilled you are on ground missions and how strong your soldiers are. If you think you will have no problem completing the mission, you can bring the timer down to 1 day and then go for the mission. Otherwise, allow for 3 days in case you need to retry the mission.
Resetting the doom clock this way will buy yourself more time to build up Xcom’s soldiers, tech, armor and weapons.
Every single Alien Facility has red boxes under it. The red boxes indicate how much the Avatar Project progress will be reduced if you destroy that facility.
Completing black-site missions will reduce the Avatar Project by -2 each time.
Skull-jacking a Codex will lower the Avatar Project by a further -2.
Skull-mining advent troops with your Specialists gives you a chance of finding Alien Facility leads. “Alien Facility Lead” is an item you can research. The Alien Facility lead will grant you access to a locked Alien Facility mission (without needing to Make Contact with that country).

Global Strategies

Engineers are the most important resource early and mid game. You will need them to excavate, build, and man facilities.
Focus on growing the Resistance network. The bigger the network, the more supplies you'll gain. But more importantly, you want to grow the Resistance network in order to unlock Alien Facility and Black Site missions. This gives you control over the Avatar Project.
Switch your priorities as the game progresses from early game to mid-game and finally late game. You'll want to get more Engineers, Scientists, Supplies & Grenades in the early game. Mid game, you will be more focused on Engineers, Intel, Supplies, Resistance Contact, Making Contact & Building Radio Stations to get greater reach over the globe. Late game, you will want more Intel and Scientists.
Save excess items and sell them when the Black Market are “interested” in them. Alien Alloys and Elerium Crystals are great items to sell if you have a lot of them and do not need them urgently to build Weapon or Armor. For alien corpses, make sure you keep enough to build “end game” items like Alien Psi-Amp or Overdrive Serum. In the late game, the black market will be a major source of Supplies for grenade, weapon and armor upgrades.
The 7 most valuable things sold on the black market are:
- PCS: Perception (+aim)
- Scopes
- Engineer
- Soldiers (major and colonel)
- Repeater
- Hair Trigger
- You’ll want the “superior” versions on your best soldiers who have the “Hidden Ability” perk
There are a total 13 continent bonuses in Xcom 2. Only six will appear every game. The 5 best continent bonuses are:
- Armed to the teeth (All your soldier’s main weapons get an extra weapon upgrade slot)
- Quid Pro Quo (Black market items cost 33% less intel)
- Spy Ring (+25% on all Intel rewards)
- Fire When Ready (All Proving Ground weapon projects are completed instantly)
- Suit Up (All Proving Ground armor projects are completed instantly)

Base Building Guide

There are a total of 12 slots for you to build facilities on. Each slot takes more time to excavate as you dig deeper.

Build the Guerrilla Tactics School first. You want Vulture and Squad Size 1 as soon as possible. Start training Grenadiers immediately and non stop through the game. Getting "Vulture" will help you collect more Elerium Cores faster, which is crucial for mid and late game
Get Proving Ground next. This will grant you access to Experimental Grenades. You want Gas, Incendiary or Acid grenades asap
Build a new Power Relay as the third structure
Build Resistance Comms next. You need to start expanding the Resistance network to have control over the Avatar Project
Build Advanced Warfare Center. You will need an engineer to man the facility if you want the +100% heal rate
Build a Workshop. It is important that you plan ahead and have at least the Power Relay and Resistance Comms adjacent to it
Build the Psi-Lab. Make sure you train 2 psi-operatives simultaneously. Take note of the Psi-Offense stat of your operatives. This stat caps at a maximum of 100. But each Psi-operative only has a 50% of reaching 100 Psi-Offense. You may want to discard soldiers who have low Psi-Offense rolls. The Psi-Offense stat increases each time an operative completes a training. The Psi-Offense stat is very important because it affects the success percentage of skills like Mind Control
Build the Shadow Chamber. It grants you access to research story missions and also tells you what type of Aliens you’ll be facing in each mission
Build another Power Relay if required. Man or upgrade your first Power Relay to maximize its power output before needing to build a second Power Relay
Build the Defense Matrix. This will really help in case of the Dark Event: “a UFO Hunts Xcom”. It can be upgraded so you get 4 defense turrets when defending The Avenger. Man it with an engineer to improve the turret’s stats. Turrets can fire twice per turn.
You do not need a Laboratory to win the game

Combat Strategies

Engage one group of aliens at a time. This will significantly reduce the chance of soldiers getting injured or dying. Be very cautious of moving forward when you are fighting a group of aliens. When you are not in combat, move forward slowly, especially in non-timed missions. Move only 1 blue tile forward and set overwatch traps with each advancement. Timed missions will require you to move fast, and may require dashing if the map is big.
Ensure you have enough grenades for every mission. You need to destroy aliens in cover, to expose and flank them.
In combat, always prioritize which aliens to kill first. Always kill the most dangerous Aliens first if your soldiers have good aim on them. The most dangerous Aliens have the highest chance to one-shot any soldier or deal AoE damage to your group of soldiers (think Heavy Mec’s grenade launcher and Gatekeeper’s “Gateway” ability). If you cannot kill them, try disabling them with EMP bombs, Psi operative’s Stasis or mimic beacons.
Always check the map size at the start of the mission. There are 3 types of map sizes. Big, medium and small. Small maps on timed missions would mean you probably have to deal with 2-3 groups of aliens at one time. You can get a sense of the map size by scrolling to the end of the map.
Flashbangs will cause Aliens to be disoriented. Aliens cannot use special abilities and grenades when disoriented. Especially useful for breaking a Sectoid’s mind control and preventing Stun Lancers from using their melee weapon.
Use your grenades to break enemy cover. Without cover, enemies will be flanked and you will gain a 40% crit chance on them with no aim penalty.
Use high ground to your advantage. You get a +20 aim bonus when your soldiers are shooting Aliens from high ground. This also works against you. E.g. Aliens get the same bonus if you’re in lower ground.
Every point of armor reduces damage by 1. If you hit a Gatekeeper for 10 damage, and it has 7 armor, it will only take 3 damage. Shredding does not ignore armor. In your initial attacks to shred armor, every point of armor will still block damage. Attacks that ignore armor include:
- EMP (only against mech units)
- Psionic (like Null Lance)
- Armor piercing rounds (ignores 5 points of armor)
Gas, fire, and acid grenades do not break enemy cover. You’ll need to use normal or plasma grenades to break enemy cover.
Be very careful of positioning your soldiers closely together. Aliens and MECs will use grenades if you have 2 soldiers close to one another. This can be a deadly mistake especially on rooftops.
Use grenades only if you absolutely have to. Grenades can destroy valuable loot which aliens are carrying. If you’ve already picked up the loot for that mission, then you can go crazy.
Take your time and be very cautious in non-timed missions. There is no timer, no urgency, and you want to make sure all your soldiers are in the best possible positions. Abuse overwatch and advance slowly to get aliens walking into your overwatch trap.
Gas grenades are extremely effective against organic targets. The poison effect will last a few turns and give Aliens a movement and -30% aim penalty
Mission difficulty indicates the number of Aliens you will have to face during the mission. Easy: 6- 8 Aliens, 3 groups of aliens. Moderate: 8-10 Aliens, with 4 groups of aliens. Difficult: 10-15 Aliens, with 5 groups. Very difficult: 15-30 Aliens, with 6 – 8 groups of aliens.
Weapon upgrades are carried forward from one tier to the next. If you have a scope equipped on your assault rifle, it will be carried forward to your magnetic rifle.
Autoloader and expanded magazines are great for Snipers especially early game. They remove the “reload” downtime in the heat of battle.
PCS Perception and Scopes should be given to your Grenadiers. They will need high aim to reliably shred and deal damage in mid to late game.
Do not excessively Overwatch in timed missions. You want to keep advancing forward and kill off each group of aliens as fast as possible. In mid to late game, you need enough firepower to be wiping out 1 group of Alien every 2 turns.
In concealment, it is not a good idea to skip packs of aliens while moving forward to the objective. The AI will track you down and you’ll end up having to fight 2-3 groups of Aliens.
Always move in 2 separate steps. Blue, then yellow. Never dash unless you are 100% sure there are no aliens ahead (meaning you have vision). Moving only one step at a time will let you to retreat into a better position, hunker down, or Overwatch if you bump into Aliens. This tactic will save many of your soldier’s from dying.
Appoint one soldier to scout ahead. This soldier should be the one with higher HP, armor or dodge. The rest of your team should advance behind him and go on Overwatch. As your scout advances one blue move at a time, make sure he has high cover (preferably) to move into.
Concealment is broken by smashing through windows or kicking down doors. Concealment will not break if there is no window or if you open the door first (manually).
If you Evac a Psi operative who is mind controlling an Alien, the Alien will stop being mind controlled and will attack you.
Always use full cover when possible. In concealment, end your move with each soldier behind cover. This will prevent alien patrols from spotting you. Alien patrols can only spot you if they flank you.
Full cover provides +40% defense while half cover provides +20% defense. No cover would mean enemies will shoot you with no aim penalty and will hit with a 40% chance to crit. Make sure your soldiers are always in cover.
Think twice before accepting a timed VIP mission. It might cost you the game if your highest ranking soldiers cannot evac in time and are captured during the VIP mission.
If a soldier is poisoned or burning and about to die, call down an Evac to save them. (In Alien Hunter, You can no longer place down evacs on units. So place down the evac first and then have your unit run into it the evac zone. This way, he can still attack and evac. Just plan where to put the evac in advance.)
Emp grenades and bombs are extremely effective against Gatekeepers, Codexes, Mecs, and Sectopods. They do up to 10 damage with a chance of shutting down enemies for 2 turns.
Keep a wary eye on rooftops. Never double move (dash) up a rooftop.
If a unit's turn is over, you can still place the evac on them and evacuate. (no longer works in ALien Hunter DLC)
Use your ranger with phantom to advance much quicker with concealment. Couple this technique with a sniper's squadsight to pick aliens off from distance. Aliens will not engage your soldiers if they are distanced enough. This tactic can work well if you have 2 or more snipers on non-timed missions.
Hacking the objective will immediately cause you to lose concealment and have a pack of aliens come and investigate your position.
Use your Grenadier's suppression skill to suppress deadly enemies who are likely to shoot with their main weapons e.g. mid game Mutons. It will punish the Alien with -50% aim and takes it out of Overwatch. The suppression ability also stacks. With 2 grenadiers suppressing the same alien, it would be -100% aim. With Holo Targeting learned, all your soldiers will also receive +15% aim on the suppressed target.
Keep an eye on the timer. There are no second chances or bonus round when it expires. This is especially true on VIP missions where you can lose your whole team if you do not evac on time. There is no “0” on the timer. The last turn on the timer is “1”.
Focus on the puppet masters, not the puppets. Mind-controlled or reanimated units all return to their original state once they lose connection to the now dead PSi alien. Alternatively, you can just kill the zombies for extra XP.
Fight one pack of aliens at a time and ensure you don't pull other groups of aliens. When facing Mutons & Berserkers, the last thing you need is another group of Stun Lancers to ruin your day.
Sectoids are vulnerable to melee weapons. Use this to your ranger’s advantage. But be careful not to rush ahead. You don’t want to pull an extra pack of aliens.
Use Hunker Down if a soldier is in a dangerous position or surrounded by many aliens. Naturally, you would want to enter Overwatch or return fire on an alien, but you'll have a low defense on the enemy's turn and might be killed. The +30% Defense and +50% Dodge from Hunker Down is a massive defense boost –don’t be surprised if all the Aliens miss.
Use environmental destruction to cause additional damage to enemies. Destroy rooftops with multiple enemies to make for easy kills and quicker progress forward. The same applies to exploding vehicles and barrels near enemies. Enemies take 2 damage per floor when falling, and 6 damage for car explosions.
If Aliens die from falling or environmental damage like exploding vehicles, you will not get any XP for the kill. However, sometimes you just need to forego the XP. Keeping your soldiers alive and uninjured is always high on the priority list.
Don't always think about looting. The risk of injury or death far outweighs the potential of picking up a new weapon upgrade. Your soldier’s life is likely more valuable than a PCS, weapon upgrade or Elerium Core (unless he’s a rookie). However, you might want to risk it if the Aliens will not be able to kill any of your soldiers.
On non-timed missions and when out of combat, ensure that your soldiers are fully reloaded with full ammo before advancing further. This does not apply on timed missions as you are sprinting through as quickly as you can.

Research and Build Order

This build will require you to keep soldier deaths and injuries at a minimum in early game. Early game, you should be aiming for “Flawless” missions or have only 1 or 2 soldiers injured in each mission.

1.   Build Guerilla Tactics School (For training Grenadiers, getting early Vulture to collect Elerium Cores, and Squad Size 1)
2.   Research Modular Weapons (For weapon upgrades)
3.   Research Alien Biotech (For Resistance Comms)
4.   Research Advent Officer Autopsy (For Proving Grounds)
5.   Build Proving Ground (To get early Experimental Grenades. Save your Elerium Cores. You will collect more with Vulture.)
6.   Research Resistance Radio
7.   Research Hybrid Materials
8.   Build Power Relay (upgrade to Elerium Conduit later)
9.   Research Plated Armor (Get Predator Armor asap for the extra item slot and HP boost)
10.   Research Psionics
11.   Research Magnetic Weapons (You dont need early mag when you have gas, incendiary and acid grenades with 4-6 grenadiers)

12.   Build Resistance Communications or Advanced Warfare Center (which first will depend on how the Avatar Project is progressing)
13.   Build Workshop (make resistance comms and power relay adjacent to it)
14.   Research Muton Autopsy (To get Advanced Grenade Launcher which lets you launch grenades further and increases AoE)
15.   Research Gauss Weapons (Get Mag Cannon first and then Gauss Rifle. You should have at least 50% Grenadiers.)
16.   Build Psionics lab
17.   Research Elerium
18.   You should now have a Grenadier ranked Captain (This will let you buy "Biggest Booms" in Guerilla Tactics School. Which will let your grenades do critical damage)
19.   Research Advanced Explosives (This can be done in Proving Grounds after Elerium research is complete. It upgrades all your grenades into bombs.)
20.   Research Beam Cannon (Get Beam Cannon first for your Grenadier heavy team)

21. Start saving Elerium Cores (For W.A.R. Suit and Experimental Powered Weapon. You want to save at least 10 elerium cores. Shredstorm Cannon is the best Experimental Powered Weapon. You should have at least 3 W.A.R. suits with Shredstorm Cannon on them)

22. Research Plasma Lance / Plasma Rifle / Storm Gun (depending on which class you use more)

23. Build Shadow Chamber

24. Research Gatekeeper Autopsy (For Alien Psi Amp which gives +40 Psi)

25. Research Sectopod Breakdown (For Gremlin Mark 3)

26. Research Powered Armor (by this time, you should already have 2 Psi-operatives with at least one of them having Domination)

27. Research and build Warden Armor

Soldiers Setup

To greatly increase your chances of beating Legend Ironman, you need a team consisting of at least 50% Grenadiers. This means if you have a total 12 soldiers, 6 of them should be Grenadiers. The more Grenadiers you have, the better. They blow up enemy cover, do great AoE and single target damage, and shred armor
You should have at least 3 Grenadiers on each mission if possible. You may increase this to 4 on timed VIP missions as they make light work of clearing a path. The strongest squad setup would be 3 Grenadiers, 2 Psi-operatives and 1 Medical Specialist
It is extremely important to keep your soldiers alive early game. You need to gradually expand your soldier count and get a good team together of Grenadier and Medic Specialists. Guerilla Tactics School should always be training Rookies into Grenadiers 90% of the time. Once you have enough Grenadiers, train Specialists
Have multiple soldiers of the same class but with a varied set of skills, load-outs and abilities. For example: If you have 6 Grenadiers, 2 of them should have Volatile Mix and another 4 should have Chain Shot
Make use of skills that give you more attack actions e.g. The specialist's “Threat Assessment” will ensure a free Overwatch. “Lightning Hands” lets your Sharpshooter take an additional pistol shot. “Salvo” for the Grenadier lets you launch a grenade and shoot in the same turn
Later in the game, you want to have at least one strong PSi Operative (with 100 Psi stat). If you can mind control an Andromedon or Archon early in a mission, its mostly gg for the aliens. Heal your mind controlled unit with your specialist and let them be on the frontlines

Xcom 2 Builds

The Best Xcom2 Grenadier Build

Grenadiers are no doubt the strongest class throughout the game. Pay extra attention on keeping them alive.
You should aim to have 10-12 Colonel ranked Grenadiers.
What Grenadier abilities should you choose when leveling up?
Corporal: Your first 2 Grenadiers should learn Blast Padding. The extra point of armor is extremely strong early game and will improve survivability. Starting from your 3rd Grenadier onwards, go for Shredder. When you reach mid or late game, retrain your Grenadiers to learn Shredder.
Sergeant: Always pick Suppression. It gives enemies -50% aim, and your soldier will take a free shot at them if they move. This skill is extremely effective at preventing most enemies from hitting you with their main weapon.
Lieutenant: Go for Heavy Ordnance. The extra grenade is extremely useful. Especially when you get to double your Plasma, Gas, Acid, Incendiary or Proximity Mine.
Captain: Go for Volatile Mix in mid game. Late game, you should have Chain Shot on 80% of your Grenadiers. You will need Chain Shot to quickly destroy high HP enemies like Sectopods, Gatekeepers and Andromedons. Use PCS Perception, Scope and High Ground to make up for your aim.
Major: Definitely go for Salvo. It lets you deal huge damage by first launching a Grenade and then taking a shot with your main weapon. You can even use Chain Shot after launching a grenade.
Colonel: 80% of your Grenadiers should learn Saturation Fire. It destroys cover while letting you hit multiple enemies. You will need 3 ammo for it so make sure you check your ammo level s often.
Your Grenadiers should be equipped with PCS: Perception, Superior Scope and Superior Repeater. Tracer rounds are also great for them. With warden armor, they can carry 2 types of grenades and 1 experimental ammo.

The Best Xcom2 Specialist Build

The second most important class in the game, allowing you to hack objectives from a distance and heal injured soldiers.
You should aim to have 3-5 Colonel ranked Specialists.
What Specialist abilities should you choose when leveling up?
Corporal: Go for medical protocol. This gives you an extra “heal” charge and the ability to heal soldiers from any distance. Keeping your soldiers alive is number one priority.
Sergeant: For your second skill, go for Revival Protocol. This is especially useful for “Unconscious” soldiers and can turn a mission around.
Lieutenant: Go for Field Medic. The extra 2 heal charges are extremely useful. With this you will have 4 heal charges per mission.
Captain: Threat Assessment is the better choice here. It grants any soldier an extra “Covering Fire” shot along with up to +40 Defense.
Major: Go for Guardian. Overwatch when it makes sense to. With Guardian, your specialist have a chance multiple Overwatch shots in one turn.
Colonel: Both Restoration and Capacitor Discharge are awesome abilities. If you have 2 Specialists, let one have Restoration while the other have Capacitor Discharge.
Equip them with PCS: Conditioning, Superior Stock and Superior Repeater. With warden armor, they can carry 1 medikit, a mimic beacon, and an experimental ammo or grenade.

The Best Xcom2 Sharpshooter Build

The 3rd most important class in the game, allowing you to snipe enemies from a distance while taking advantage of high ground (+20 Aim).
You should aim to have 2 Colonel ranked Sharpshooters.
What Sharpshooter abilities should you choose when leveling up?
Corporal: Go for Long Watch. This allows your Overwatch shots to trigger even from long distances.
Sergeant: Lightning Hands would be more useful than Deadeye. It gives you a free pistol shot that can turn the tide of a battle.
Lieutenant: Go for Quickdraw. This allows you to actually take 2 pistol shots every turn. 3 if Lightning Hands are off cooldown. It is extremely useful for damaging multiple enemies.
Captain: Go for Faceoff. Kill zone requires very good positioning and does not trigger properly sometimes. Faceoff is more reliable and works well with Experimental Ammo
Major: Learn Steady Hands. Most of the time you will be already in a good sniping position and should be taking shots every turn. The +10 aim and +10 crit only makes you more deadly.
Colonel: Go for Serial. This skill allows you to deal massive damage in one turn by taking down multiple enemy threats.
Equip your Sharpshooter with PCS: Perception, Superior Hair Trigger and Superior Expanded Magazine. (early game, you can equip them with Auto-Loaders). They also do well wearing W.A.R. Suits with Plasma Blaster or Shredstorm Cannon.

The Best Xcom2 Ranger Build

I consider Rangers to be the weakest class. They are not very effective because they have to be in close range and that means the risk of pulling extra packs of aliens. They have some nice skills like Conceal but this is not needed to beat Legend Ironman.
You should aim to have 1-2 Colonel ranked Rangers.
What Ranger abilities should you choose when leveling up?
Corporal: Go for Blademaster early game. This allows you to one-shot Sectoids with your blade. Blademaster gets less useful as the game progresses, so retrain your Ranger to learn Phantom at mid-game.
Sergeant: Go for Shadowstrike. This will allow you to one-shot aliens from a good distance.
Lieutenant: Conceal and Run and Gun are both great skills. I would personally pick Conceal. It just synergizes better with Phantom and Shadow Strike and a defensive playstyle (which is what you should be using in Legend Ironman).
Captain: Pick Bladestorm. This skill is extremely powerful in close encounters. It will trigger on every enemy that is next to you. Bladestorm triggers on any enemy action (movement or attack), granting you a chance of killing the enemy before they can pull off their attack.
Major: Learn Untouchable. It can save your Ranger’s life.
Colonel: Go for Rapid Fire. This is one of the most powerful skills in the game. It allows the Ranger to take two shots at an enemy every turn. Great against high HP enemies. This skill has no cooldown and give a -15 aim. Make up for the aim penalty with close range, scope or high ground advantage.
Equip your Ranger with PCS: Conditioning, Superior Scope and Superior Laser Sight. They also do well wearing W.A.R. Suits due to having the need to be on the frontlines.

So now you have a strategy to beat Legend Ironman. But you still wont be able to beat it until you you become an expert in ground missions. That comes through experience. Prepare to lose many missions before you are able to master them.
Good luck, Commander.

Also check out these articles:

10 Things Firaxis Should Do To Make Xcom 3 Epic

All X-Com Games, Ranked Best to Worst

Credits to Rambostein for the excellent guide.