Psionics - Main article
Countering psionic attacks and tactics:
The former doctrine on psionically attacked soldiers also applies to soldiers who have been psionically screened. Namely, soldiers weak in psi-strength or who have become victims of psionic attack should be sacked or re-assigned at the earliest opportunity for the safety of the rest of the squad. If retained on active duty they should never be knowingly sent on missions against psionic capable aliens. Veteran soldiers who are psionically weak but otherwise worth keeping can be assigned to a secondary craft or interception base, strictly for use on missions against Mutons and other non-psionic aliens.
JellyfishGreen: I tried jotting down the names of the puppets as a reminder to fire them later, or use as decoys.
Covenant: Another good way is to go right from the mission's conclusion to the soldier menu and add a symbol or word to their name so it is instantly recognizable who got mind controlled, and who successfully resisted. Handy for picking subjects for psi-training before you know their strength levels.
Some commanders forgo any chance of reaction fire, and have all soldiers drop their weapons at the end of the turn and pick them up on the next turn. Should any soldiers be mind-controlled in the intervening alien turn, at least they'll be unarmed.
Test results tell us the soldier with the highest chance of a succesful psionic attack is always chosen as the victim, even if he's out of line-of-sight of either enemy or ally. (The game AI is skipping any LOS requirement) This usually means the aliens concentrate on the weakest psi defence soldiers, though they will switch targets depending on distance. - Psi-puppet soldiers should NOT be used as alien hunters. Disarm them as soon as possible, preferentially before the mission.
If such soldiers are deployed against psionic capable aliens, they may still have use in limited roles. Do not give them any weapons or grenades. Well, maybe smoke or proximity grenades.
- Unarmed medic, equipment operator, ammo carrier. If controlled, they cannot injure other soldiers. If panicked, they'll drop the equipment, if placed in their hands.
- Non-lethal weaponry. Small Launchers prevent injury of other soldiers but the risk of control and loss of tactical advantage remains.
- Stun Rods are non-functioning weaponry in the hands of the aliens. Any soldiers under alien control WILL NOT ATTACK using them.
- Miner. Arm them with Proximity Grenades. Unlike those pesky aliens, your agents are smart enough not to get blown up by these things, right? (Just pick them up off the ground). Beware that your panicked soldiers seem to be drawn to Proximity Grenades like iron filings to a magnet. Probably due to Murphy's Law.
- Decoy. The unarmed soldier lets themself get mind-controlled rather than shot. If they are under mind control, the soldier will often be spared by the alien. Every mind-control attack on the "decoy" is one less attack on the rest of the squad and one more psionic alien kept busy. Note your other soldiers may shoot a controlled decoy on sight, and the aliens will shoot a panicked decoy on sight. An extremely risky tactic for the soldier but survival can be extended by blockading the decoy into a closet with other soldiers or tanks and turning your back to them. (which is ridiculous since you are taking 2 soldiers out of combat to prevent losing use of 1 soldier during combat)
- Jack of all trades. Soldier is meant to be a decoy, and carries, Stun Rod in hand, and flares, medkit and smoke grenades. Soldier is also considered "expendable" and thus fulfils role as forward scout during scary situations.
- Launcher Operators. Simply a soldier with a launcher and no ammo. The soldier either stands on a pile of ammunition, or is handed the ammunition on demand in combat. Once the weapon is loaded, the round is immediately spent before the end of the turn. This way, if controlled, the soldier will have an empty weapon and thus be harmless. This allows the weak willed soldier to contribute somewhat to the fight whenever you regain control of them.
- Suicide Bomber. Give this troop no equipment. March him towards a heavily guarded alien ambush. Just before walking him into it, have someone else arm a Heavy Explosive, throw it to him and make him pick it up. Have him walk into the trap and get mowed down by hidden alien reaction fire. End turn. BOOM.
If there are two or more psionic aliens, you may need more decoys to keep them all busy.
Stubbs: According to the Mind Control section of this wiki, XCOM operatives do not reaction fire at mind-controlled friendlies. Which is correct?
Kill the puppetmaster.
Find and kill the alien doing the mind control. This will free those who were under its control. The mind controller is frequently the highest-ranking alien you're facing, which means you'll likely need to penetrate the command center of the structure you're facing.
Remember that killing the aliens' ranking officers imposes a major morale penalty to the invaders, another bonus that shouldn't be underestimated. Many commanders have seen a seemingly invincible, mind-controlling attack force reduced to panic in the instant their commander is shot down. Even against Ethereals, all of which have psionic capability, this tactic is useful, since it will often buy you a round or two before other units start using Psionics and can panic even them.
Must... Fight... Harder... DIE!
If you can force a very successful round of attacks, the morale penalty this imposes on the aliens may bring on panic, which would bring a temporary stop to their psionic attacks. Such a round also raises the morale of your own troops, which will temporarily help combat panic attacks.
Roll with it.
Kamikaze tactics have also been used but cannot be recommended here.
HWP's can continue to be used in all roles against psionic capable forces as they are immune.
If all forces are equipped with Power Suit, which is proof against light ballistic weaponry, standard rifles and pistols can be freely issued with little risk of lethality even if counterused. Note Ethereals are less affected by these weapons than Sectoids. For them, we recommend the Auto-Cannon/HE.
- JFG, with credits to the adventurous NKF-sensei whose field reports I freely draw from. --JellyfishGreen 14:50, 19 Apr 2005 (BST)
-MikeTheRed: In my experience, laser pistols can hurt you in flying suits. Specifically, if you're shot in the back. So they are great for "firing squads" (all your guys facing MC'd aliens), but not when aliens might MC you. (And don't turn your back when doing a firing squad!)
-NKF: " Just to add to this, a laser pistol, with 46 laser, does between 0 - 92 damage (See: Damage). Therefore, only your front plates will be truly invulnerable to laser pistol damage. On the other hand, you have a chance of being damaged from pretty much every other direction, and you cannot always guarantee that you'll be facing your attacker at all times.
The only real consolation is that laser pistols won't kill you outright for each hit, but lots of little hits can indeed build up to a lot of damage. I'd much rather recommend an autocannon/HE or the standard pistols/rifles for this exercise. Direct hits from the ACHE can probably cause a tiny amount of damage, but the ammo will not be unlimited like the laser pistol, and the autocannon is also the slowest burst weapon in the game, despite its name, which gives you time to get away and seek cover. Another bonus is that it works a lot better on superhuman ethereals than the pistol/rifle! "
You won't know exactly what your soldiers' psionic strength are until you run them through some form of screening process, running them through a Psi Lab in batches of 10. Soldiers with a high Psionic Strength (80 or higher) should be trained further and kept in the "rear guard" during combat. Do not use them as scouts, or front line troops -- they will soon become your most valuable soldiers.
After a month or two of Psi training, your best soldiers will be able to mind-control weaker aliens, such as Mutons. Your soldiers' Psi Skill can be increased very quickly by equipping them with Psi-Amps, leaving them in the Skyranger, and having them attempt to panic units every chance they get. See Experience Training#Psionic Skill training for more details.
Pre Psi-Lab Screening
An efficient, if brutal, method for screening your troops for psionic ability is to use the first psychic alien you encounter. A supply or terror ship with a Sectoid Leader is recommended.
Kill all the lower ranked aliens, and secure the UFO using usual tactics (a psi-decoy is useful in this regard). If the ship is reasonably intact, the Alien leader will not usually leave the bridge, even after turn 20.
Gather your troops into the UFO, get any soldiers who are targeted to throw their weapons, then stun or kill the most susceptible soldiers until the remaining soldiers are immune to Mind Control, and the Alien frequently fails to panic units (you can check this by keeping track of morale).
- A side benefit of this is bravery training. If the weaker soldiers are killed rather than stunned, those who remain will very quickly reach 60 or 70 bravery. Leaving the highest ranked soldiers at home, or using the bravest soldiers to target the rookies, will help in this regard.
A more precise but much more tedious addition to this tactic is to arrange your troops in a line intersecting the UFO. Any soldiers attacked move away until another soldier is attacked instead. You may still have to stun or kill the weakest soldiers as the map may not be large enough.
- At the end of this process you will have your troops neatly sorted by psi-strength with the distance being proportional to the difference.
- If the line ends directly under the bridge and the closest soldier is never attacked, this will give you a lower bound for the psi-strength of your entire (surviving) force.
Given five large, Sectoid UFOs, this method will, on average, give you a Skyranger full of elite (>80 PST) psi warriors all ready for training when you finally build a psi-lab.
My New Pet Alien
Some skilled psionic operators have had success with simply attempting control of every alien encountered and disarming them, then using the controlled alien as a scout to find more aliens, then controlling the newly discovered alien as a new scout and leaving the old one for a mop-up squad, repeat process as TU's permit.
Easiest actions with a controlled unit are movement and firing or dropping the held weapon. It is possible but tricky to do more (see Alien Inventory Trick.) Disarmed aliens make for excellent Experience Training fodder.
Remember aliens will revert to alien control unless re-aquired on the next turn.
Controlling the Board
Once you start taking control of aliens that are psionic themselves, this has a certain avalanche effect as you can spend the alien's TU's on mind control as well. As noted in Exploits you do have to throw them a spare Psi-Amp to take advantage of this.