X-COM Field Manual 31-1

[NKF]

- Throwing grenades into walls -- this is the usual one where you throw items into the corner walls of a ufo. You can even do this with unconscious soldiers if you want so that when they wake up, you can get them to step into the ufo.

 

- Throwing items up through ceilings -- try it. Launch a new game in either UFO or TFTD, then when your first mission starts, 'throw' something directly above you. You can also try it at slight angles too. You must use a slight angle to throw items through really tall ceilings. I don't think the game is able to properly handle colision detection for throwing items up at the ceiling. Still, it's a great way to get unconscious units or grenades up to a level you cannot get to in those rare cases where you accidentally destroy all the stairs.

 

- As for walking soldiers through solid objects - it only works for soldiers who cannot fly. The easiest place to experiment with this is on the lightning. Have a soldier stand at the bottom, right next to the stairs. Now, on the same level, select the tile underneath the power unit, or any one of the chairs. The soldier will walk up the stairs and walk right into the chairs or the power unit. To walk through UFO walls, it's the same, but you need to use an upper level. Climb onto the roof of a building, and while on the same elevation, select a location just above the UFO or the wall itself. The soldier will proceed, drop, then walk right through the wall (only works with the walls facing away from you). A very similar method can be used by ground troops to climb some of the rock formations in the mountain region.

 

Flying soldiers can do something similar, but they have to float up into an overhanging 'wall'.

 

- NKF

[Fox]

Wow... in all of my days of X-COM I never knew you could do that... Thanks for enlightening me NKF!

[JellyfishGreen]

"WE CAN FLY. WE CAN CONTROL MINDS. WE CAN SHOOT WHAT WE CAN'T EVEN SEE. AND NOW WE CAN WALK THROUGH WALLS."

 

Snakeman to Snakeman Commander: <What the heck ARE these things?>

Snakeman Commander: ::panics::

[NKF]

Oh I don't know, walking through walls is usually a bad idea. I mean, it's rather embarassing to step through a wall only to run out of TUs in front of several grinning aliens.

 

Oh and another one. I mentioned this one before in one of the older threads. Explosive shells (incendiary, HE and stun) fired at the ceiling will only cause damage to the level above you. That is to say it's perfectly safe for a soldier to fire a blaster bomb directly up at the ceiling at and not suffer any consequences[1].

 

I don't really treat this one as a 'cheat', since if done in the barns, the ceilings do get destroyed. It's not your fault the ceilings of the ufos are so tough that only something as powerful as a heavy plasma or a blaster bomb will make a hole in them. Still, this is an excellent tactic to use in intact abducter and supply ships, due to the nature of the 'camping' alien that always waits in the command room. Just get underneath it and fire some shells, rockets or stun bombs up at the ceiling and poof, the alien's safely dispatched. Could work wonders in any multi-level ship too, if you've got a motion scanner to detect where the aliens are.

 

All right, I think that's enough of the 'unusual' for now. Let's get back to the good stuff eh?

 

- NKF

 

[1] Before I forget -- you might want to mention something about the blaster bomb duds that are left behind after firing the blaster launcher via reaction fire (yes, rare, but it can happen) or when using only one waypoint.

[Hobbes]

OK, let's see....we already had aliens, zombies, telepathy, mind control, telekinesis and ray guns on this game.

 

But now you can also walk through walls and other solid things????

 

I'm starting to think this game sounds more like "The Paranormal Chronicles" or something like that. Please feel free to post your sightings of the Loch Ness Monster while playing the game

[NKF]

It's just a collision detection bug. Besides, you can't just walk through any wall -- they have to be walls that are really objects made up to look like walls (it's hard to understand without looking at the data in the map files. Suffice to say, they're the walls right next to the tiles that look empty, but cannot be walked into, since the wall is really occupying the entire tile). I'm guessing the game's trying to detect a collision of solid objects on the level you told your soldier to move at and does not consider the soldier's change in elevation.

 

*sigh* This is what happens when you notice weird things happening and suddenly figure out how to replicate it... too much information.

 

Oh well, might as well classify all these unusual 'features' under bugs and be done with it.

 

Yeah, the game is full of sci-fi cliches (thank goodness it doesn't feature time-travel! ). If it were a movie, I'm sure it would have been featured on Mystery Science Theatre 3000 by now.

 

- NKF

[Fox]

[1] Before I forget -- you might want to mention something about the blaster bomb duds that are left behind after firing the blaster launcher via reaction fire (yes, rare, but it can happen) or when using only one waypoint.

 

I was always under the impression blaster launcher dudes couldn't use reaction fire... I have NEVER had that happen. And I usually have Hovertank/Fusions around aliens a lot, and I think they would have reacted by now... I'll have to go try this out.

 

Edit: fixed quote

[JellyfishGreen]

Explosive shells (incendiary, HE and stun) fired at the ceiling will only cause damage to the level above you.

 

<snip> Still, this is an excellent tactic to use in intact abducter and supply ships, due to the nature of the 'camping' alien that always waits in the  command room. Just get underneath it and fire some shells, rockets or stun bombs up at the ceiling and poof, the alien's safely dispatched.

I'd like to name this tactic "Serving the eviction notice".

 

"Pillar Shaker" comes to mind too... although in Big Trouble in Little China, this tactic just dumps chunks of ceiling on your head.

[Spaceman42]

Okay, let me clarify my intentions with this project.

 

Basically, I want to make a "military" tactics guide, with greater reference to "real-world" than UFOD tactics [but still applicable to both]. Thus, I want to avoid references to "points", to unresearched technologies, and to stuff not "known" at the beginning of the game.

 

[This isn't to say that that stuff won't be added in; I'm just trying to make it easier on myself by not including it. It's a headache, trying to convert point-values into "real-world" terms; basically, all you can say is how many shots they can usually take before they go down...]

 

So then, any "strategies" that can't be reproduced in real life will be mentioned in an "addition" - a separate file detailing UFOD tactics that wouldn't work in the real world - and any early-encounter stuff will be added in whenever I think it's justified / have the time. [Grays and the like will be put in the Speculative section; I need more "speculative technologies" ideas, just so it doesn't look like I'm making speculations based on what *does* happen.]

 

Hopefully that clears things up some.

 

Cheers,

 

-K

[Hobbes]

Speculative Ideas

 

- Alien weaponry

 

In all armed confrontations that have occurred, our forces have reported that the aliens use highly advanced weapons that unleash tremendous destructive power. Some of the terms used by our troops on mission debriefings to describe the firepower of such weapons have been: "ray guns", "flashy beams", "green death" and others. The reports have also stated that our own Kevlar body armor is useless against the discharge of the alien handguns, which seem capable to destroy any man made material.

Although we can only speculate in the inner workings of such weaponry, the general consensus is that the aliens possess an energized particle beam weapons. Such devices have been theorized before on Earth but have never seen pratical applications, due to power restrainments and beam dispersal, and even then those were restricted into large gun emplacements since it has been considered impossible to apply those concepts to handguns at our present technical level.

Therefore it is recommended that all X-Com personnel act with extreme caution and care while engaging in armed confrontations with the extraterrestrials until more is known about those weapons that hopefully allow our scientists and engineers to develop viable protection gear.

 

Just got inspired

[JellyfishGreen]

Fair enough. To paraphrase, this is the 1998 issue of this manual. Maybe this manual should have little or no "Speculation Section".

 

All references to "skill points" will have to be in a separate document, XCOM Personell Administrator's Guide. All references to _specific_ alien tech will have to go into After Action Reports and Analysis.

 

This Field Manual is purely about How to Fight with the Tools we Got.

 

 

 

hmm. conventions required, like 1 meter = 1 game square?

[Spaceman42]

Speculative "In-The-Field" stuff, I was thinking. I mean, if you were a scientist speculating about what sort of alien you're going to run into and what kind of weapons they'd have, what would you come up with?

 

And what kind of weapons do you think would be developed in a year or so of intense research? [Not neccessarily *happening*, though.]

[NKF]

How about UFO sightings? You could make up snippets of newspaper articles talking about people seeing flying oblongs and other geometrical shapes in the sky. Perhaps even a few mission reports from the Kiryu Kai's failed attempt at intercepting UFOs. With these, you could indirectly mention some details about the UFOs involved such as the dimensions and speed and the reach of their plasma rays. More accurate details could be included in later documents.

 

- NKF

[NKF]

I don't know what possessed me this afternoon, but I ended up writing the following unfinished descriptions of your starting weapons. I fell asleep by the time I reached the rocket launcher. As you can probably see, my grasp of military lingo is not all that great.

 

Don't worry about the notes. Just put them in to clarify some bits.

 

- NKF

 

---

 

Pistol

 

The X-Com semi-automatic handgun is one of the fastest single-shot weapons in X-Com's entire arsenal[1]. Though it does not feature a burst mode like some modern handguns, it's so fast that it almost feels like it has one.

 

Soldiers have often commented on how similar the pistols are to the rifles and Heavy Cannons in terms of accuracy. The snapshot hit ratios for all three weapons are identical, even up to distances of 60[2] meters. However, the pistol falls short for carefully aimed shots because it lacks the advanced aiming mechanisms that come standard issue with the rifles and cannons[3]

 

The pistol is highly effective against light armoured enemies and is not recommended for use against heavy armour.

 

Pros: Light, fast firing, compact, one-handed, very cheap

Cons: No burst mode, low stopping power, medium clip capacity, low aimed shot accuracy

 

Notes:

[1] It's true. It is the fastest. For both snap and aimed firing modes.

[2] Using the 1 tile == 1 meter analogy. The largest map in UFO/TFTD is 60x60 square.

[3] The pistol's the second least accurate gun for aimed shots in the entire game. The worst is the laser pistol.

 

 

 

 

 

Rifle

X-Com's staple semi-automatic infantry weapon. Each rifle can carry 20 6.7mm armour-piercing bullets and comes with a standard issue scope that allows for accurate shooting over a distance of 60 meters or more. It can be fired in single or burst modes.

 

However, we have had the following complaints:

 

1. It's too weak. Despite being of a better calibre than the standard X-Com handgun, it only offers a miniscule increase in stopping power.[1]

2. The cumbersome design of the rifle makes it difficult for quick aiming. [2]

 

Like the handguns, the rifles are only recommended for use against light armoured infantry[3].

 

Pros: Accurate Aimed mode, Burst mode, large clip capacity

Cons: Hard to aim, medium burst accuracy, low stopping power

 

Notes:

[1] Only +4 extra points to be exact.

[2] As slow as the Heavy and Auto Cannons at 80%

[3] Sectoids, Snakemen, Floaters. Anyone with little to no armour.

 

 

 

 

Heavy Cannon

This powerful weapon uses high calibre shells that come in three varieties:

 

Armour piercing: Effective at penetrating heavy armour.[1]

 

High Explosive: Contain slightly more C4 than a conventional X-Com grenade. But unlike the grenade, HE shells can be delivered a much greater distance.

 

Incendiary: Filled with a phosphorous compound that spreads a blanket of fire over a small area upon detonation. The initial impact causes minor damage and the flames will sometimes stick to anyone caught in the impact zone.

 

Snapshot hit percentages for marksmen with the Heavy Cannon are identical to that of the rifle and pistol.

 

Aimed shot hit percentages, while not as good as the rifle, are surprisingly better than the pistol despite the weight and bulkiness of the weapon.

 

Due to the slower shell loading mechanism, the wait between each shot tends to be very long.

 

Pros: Good stopping power, varied shells

Cons: Heavy, Slow firing, small clip capacity, no burst mode.

 

Notes:

 

[1] Assuming we haven't yet encountered heavily armoured aliens.

 

 

 

Auto Cannon

This is the automatic version of the Heavy Cannon. It retains the versatility of the Heavy Cannon and features a larger magazine as well as the capability for automatic fire.

 

Drawbacks worth noting.

 

1. To compensate for the larger clip capacity, the bullet calibre has been reduced slightly.

2. To prevent the weapon from overheating, the Auto Cannon's rate of fire is greatly reduced in burst mode[1].

3. The Auto Cannon is much heavier than the Heavy Cannon, which also makes it slightly harder to aim with.

 

Despite the drawbacks, this weapon is truly devastating against lightly armoured opponents, particularly when using a belt of high explosive shells.

 

Pros: Burst mode, varied shells, high stopping power, large clip capacity

Cons: Very heavy, very slow burst mode

 

Notes:

[1] This is true. The Auto Cannon is the slowest auto-fire weapon in the entire game. It's also the 2nd least accurate burst mode

 

 

 

 

 

Rocket launcher

Blah blah blah, fill in the blanks[1].

 

 

Pros: Very accurate when aimed, very high stopping power, varied rockets

Cons: Very heavy, small clip capacity, very slow firing, no burst mode.

 

Notes

[1] This weapon is the most accurate aim-shot weapon in the entire game, at 115% accuracy.

[JellyfishGreen]

NKF falls asleep..and still manages to add a footnote

 

Given that the original manual date is 1998, perhaps we could have a second manual containing the addendums on how to use the alien tech?

 

Addendum: March 1999: Beam Weapons: Heavy Plasma

 

The retrofitted captured Heavy Plasma Rifle is a powerful squad support weapon but light enough that some squads have issued the weapon to half their members. In Burst mode this weapon is easily capable of penetrating masonry and even inner UFO walls, a level of damage that would normally require explosives, and some squaddies have found this a convenient means of forcing entry. The 30 rounds are usually more than sufficient for the typical engagement.

 

Pros: High stopping power. High penetration power. Light weight.

Cons: Not as accurate as laser rifle.

 

Addendum: August 1999: Launched Weapons: "Blaster Bomb"

 

The Blaster Bomb is an OUTSIDE toy.

[NKF]

I wrote that footnote first, since I was wanting to stress how accurate a rocket launcher is when aimed (it's got a whopping 115% accuracy). Then I fell asleep.

 

By the way, the heavy plasma actually beats the laser rifle for accuracy -- but it's slower than the laser rifle.

 

Thought I'd have another go at this prosy stuff:

 

Heavy Laser

 

Despite the development of an advanced recyclable power source that now powers our new laser guns (for hours on end if necessary if our field results are anything to go by), the researchers in the laser programme have hit a plateaux. It's the same old problem that's plagued laser research for many years. There's just not enough power.

 

By attempting to supercharge the laser revolver, the scientists were forced to double the amount of power recyclers required to power the gun. This resulted in the larger but more versatile laser rifle, which quickly became an instant hit with the grunts. Attempting to perform the same procedure on the rifle has failed to bring forth very many positive results. Not only has it increased the weight and bulkiness of the gun, it only offers a minimal increase in energy output. Also, to prevent the gun from overheating and exploding, the burst mode has been permanently disabled. This last bit of bad news was not very well received by the soldiers.

 

Further attemps to increase the power output of the gun, dubbed the 'heavy laser', resulted in a weapon that could only be moved about by towing it about on wheels. Since this is impractical as an infantry weapon, the heavy laser will be left 'as is' and any further developments will go into developing a heavy laser capable of being mounted onto existing HWP systems. The blueprints for the tank/laser should be ready for submission about the same time the blueprints for the craft laser cannon and the Lightning Mk I are handed in.

 

It is rumoured that the reluctance to further the laser project in the direction of hand-held infantry weapons is a direct result from the reports of the alien plasma weapons (and presumably the jibes) from the department in charge of researching alien artefacts.

 

Pros: Powerful,

Cons: Heavy, Very slow, no burst mode, poor accuracy[1]

 

[1] The loss in accuracy is not as bad as it sounds. It's better than the laser pistol. Still, the loss in speed and low increase in power output seriously prevents it from being a contender with the heavy plasma.

 

- NKF

[JellyfishGreen]

So yeah. Spaceman42 is still Chief Editor. Whatcha want us to write about now, Chief? Can you put the material so far into an updated manual?

[NKF]

Yea, verily, we can keep up the brainstorming as we go along. At the moment, however, something specific to start on might prove to be more productive.

 

---

 

After scanning through AGX for any new threads, one of the more recent topics caught my eye. Deployment strategies.

 

I recall we had a similar discussion a while back on how to deploy at a hot LZ. It might be worthwhile to resurrect that thread for a bit and grab anything applicable for the combat manual.

 

- NKF

[Psy Guy]

Rules of Engagement

 

Civilians:

In the event of an assult on an urban setting protection of civilians is the number one priority. In the event of armed civilians engaging the enemy it is advised to use nessicary caution and avoid armed confrintation. While soldiers reserve the right it is not adviced to engage civilians in armed combat.

 

Property Damage:

In the X-Com charter it is stated that while not ignored, damage caused by X-Com engagement of enemy forces of any enviornment will be forgiven and X-Com will not be held accountable for cost.

 

(More to come)

-PSY GUY-

[Spaceman42]

I'd'a said more stuff if I hadn't been burdened with homework for the last, oh, week. I ought to have some stuff together by mon. hopefully...

[Fox]

This would be like a work of fanfic then... I think some of us should get together and make like a tactics guide... like a GAME tactics guide. Complete with screenshots and everything as examples of different tactics. Know what I mean?

[JellyfishGreen]

Well, Fox, every topic so far has in fact given a hint on how you can win the game. Eg. "XCOM not accountable for cost of property damage" = You are not penalized for blowing up buildings, so raze the stables to get that snakeman.

 

We've just been pretending it's advice to the soldier, not the player.

 

Screenshots with big red arrows drawn on would work fine in this manual, if you want to do some, we'll just say they're aerial camera views marked up by staff. Top-down tactical schematic views, like football plays, or NKF's "UFO Lurker Lure" tactic, will also be appropriate.

[JellyfishGreen]

Warning this may make your brain hurt.

 

Addendum: February 2000: Psionics

==================================

A brief working theory:

----------------------

 

The psionic research group has theorized a "conchfield", or field of consciousness, is put forth by all sentient beings. The scientists speculate that this field exists as an energy on a plane coexistant with our own space but undetectable by Earth technology. They refer to this as "conchspace".

 

Normally the patterns of a conchfield are individual and isolated. They rise and fall with the electrical brain waves we can measure. No two conchfields can physically superimpose because they are tied to separate minds and bodies in our own space which cannot superimpose. However, there is also some energy which can travel freely in this conchspace and interact with conchfields. Whether by some geometry of conchspace or of our own space, if this energy is continually exchanged between two conchfields, the conchfields start to synchronize patterns.

 

It is speculated that occasionally this "standing wave" effect occurs naturally, and this has given rise to limited and fleeting psychic phenomena dismissed as superstition.

 

However the alien technology gives the additional power and control to turn this phenomena into a useful tactical advantage.

 

Mind Probe:

-----------

These allow an impression of a subject conchfield to be briefly superimposed on the operator. The transmission is mostly one-way and usually the subject has a brief sensation of an altered state or a wider consciousness but is not otherwise affected. The information gathered is stored in the mind probe until accessed. This can convey information as general as a feeling of high morale to as specific as the subject's last assessment of their armour. The operator does not need to be trained but must know the physical location of the subject to within a meter. The probe takes several seconds to perform its scan so patience is required.

 

Squads report successfully approaching and capturing an alien with no resistance after first determining its fatigued state with a mind probe.

 

Psionic Amplifiers:

-------------------

The "psiamp" or psionic amplifier can set up a feedback loop between two conchfields so that the operator can attempt to tranfer thought between their own mind and the subject. The physical location of the subject must be known to within a meter. The operator must be trained.

 

The amplifier is geared for two forms of psionic attack, the first a projected feeling of fear, apprehension, or panic and the second a near-total control of the subject's mind and body. The subject usually perceives this as a change in their instincts or low-level desires that leads them to change their higher-level behavior, similar to hypnosis. The subject may be behaving completely counter to the norm, such as preparing to fire on their own forces, but as their own sense of self is being suppressed, they may not even be aware they are behaving strangely. The subject's companions, on the other hand, can recognize the change almost immediately. Symptoms include vacant stares, inappropriate emotions or lack of emotion, and unresponsiveness.

 

The subject's perceptions are also fed back to the user, allowing them in effect to look out through the subject's eyes. This on its own gives the user a tactical advantage if they can gain knowledge of how their opponent has deployed their forces, and also allows them to locate and choose additional subjects.

 

The alien robotic ground support weapons ("Cyberdisks" and "Sectopods") have psi receiver circuits which allow them to be directed psionically by their squads, much as our own HWP's use a radio link.

 

A distraction to the user may allow the subject to break the feedback loop and re-establish their sense of self. A user will also find it hard to maintain or even establish a loop if the subject has high psi-strength, although training can help.

 

Training:

---------

The psionic training facility uses a sensitive psionic receiver and a fixed version of the psiamp. The electronics recognize the projection of a trainee and provide auditory feedback through the headset. The trainee attempts to project their impressions of this tone along with their other thoughts. The stronger the feedback loop, the stronger the audio tone. Half of this feedback loop is thus psionic and the return half electronic.

 

Training consists of both projecting and resisting - projecting is attempting to establish a feedback loop with a remote field, and resisting is attempting to break a feedback loop initiated by a remote field. In combat this corresponds to attack and defence. Psionic skill in attacking is also developed by moving the target, which forces the trainee to be effective in rapidly translating between normal space and consciousness space and performing the projection accurately. Defence depends mainly on psionic strength, a passive ability.

 

Each station is screened from the others. The headset also muffles external noise. Special goggles flood the eyes with a soft red light. It is in this sensory deprived trance state that projection comes most easily. As the trainee becomes more skilled at initiating and establishing an interface with the psiamp, the sensory deprivation equipment can be reduced and eventually removed. Soldiers are then able to go into this trance state without aid in the field.

 

This training serves to both screen soldiers for latent psionic ability and to exercise that ability. For several weeks, even the best soldiers may not be able to grasp what is asked of them, so a full month is required for proper evaluation.

Psionically gifted soldiers are of course extremely valuable assets. Due to the high casualty rate of XCOM, commanders have recommended that the soldiers undergoing training should be given less hazardous duties or taken off active duty for that month, until at least a preliminary screening report is available.

 

Deployment:

----------

Psionically strong but unskilled soldiers can be used in any scouting or fire support role. As per standard doctrine, they should relay all information about the position of the enemy as efficiently as possible; this allows both support fire and psionic attacks to be brought to bear.

 

Psionically skilled and strong soldiers should be kept out of direct combat to allow them to concentrate on using the psionic amplifier. They do not need to leave the landing craft to carry out their duties, so leave them here unless the craft is under attack.

 

It may be useful to assign them an aide who can evaluate targets with the Mind Probe and help determine the best use of a psionic attack.

 

Preferred targets would be higher-ranking units, psychically capable units, or heavy weapons units. It is possible to control any alien, including the psionically controlled robotic units. 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 determine the next target unit, then taking the next target unit and leaving the previous unit for a mop-up squad.

 

Easiest actions with a controlled unit are movement and firing or dropping the held weapon. It is possible but tricky to do more.

 

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 dismissed 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.

 

If such soldiers are deployed against psionic capable aliens, they may still have use in limited roles.

1) Unarmed medic or equipment operator. If controlled, they cannot injure other soldiers, but they can give away their positions.

2) Support fire. A riskier tactic, where the soldier provides long-range support fire for a spotter and endeavors to never come within sight - and thus control - of an alien.

3) Non-lethal weaponry. Stun rods or stun guns again prevent injury of other soldiers but the risk of control and loss of tactical advantage remains.

4) Diversionary. An extremely risky tactic for the soldier, this role is similar to that of an unarmed scout. Attempting to separate themselves from the main group, the soldier attepmts to get themselves mind-controlled rather than shot. If they are under mind control, the soldier will often be spared by the alien; and if they are far enough away, they won't be revealing tactical information about the rest of the squad.

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.

 

Heavy Support Weaponry should be assigned to soldiers with high psionic strength to prevent its counteruse.

 

If all forces are equipped with Powered Heavy Armor, 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.

 

- JFG, with credits to the adventurous NKF-sensei whose field reports I freely draw from.

[Hobbes]

The warning was a good idea

 

The text is excellent, there's only one thing that I disagree with.

2) Support fire. A riskier tactic, where the soldier provides long-range support fire for a spotter and endeavors to never come within sight - and thus control - of an alien.

 

This is slightly incorrect because the aliens can perform psi attacks on any of your soldiers even if they are only seeing one of them. The best example of this is when you're assaulting a medium or large UFO and have cleared the terrain outside. The Sectoid Leader inside usually starts mind blasting not only the soldiers spotted by the aliens on the inside but also the ones outside.

A couple of lines using your conchfield theory should do the trick of explaining it

[JellyfishGreen]

Darn it, just when you think you have a self-consistent, utterly unprovable rationalization...

 

Edit: So then. Delete "diversionary" tactic and add "one sighting, one shot, one kill" doctrine when facing psionic capable EBEs, esp. Ethereals, as any Ethereal who is allowed to observe even one member of a squad has the ability to determine the position of and attack any member at will.

 

This "rapid location scan" is a feature of the alien implants we have not been able to duplicate in our psi-amps. The only way we have of blocking it so far is through the base "mind shield" which is not presently portable.