Anti Alien Infiltration.

[Tyro]

Assuming you have no problem with uh..."re-negotiating" funding from infiltrated countries

 

Copy iglob.dat and diplom.dat from a previous save game to the one where the aliens have infiltrated a country.

 

Voila! Your contract has been re-negotiated

 

Note this restores dates from the save slot you copied from. So this can be useful if you want to bring up the Psi training window within a few days, for example.

[Zombie]

One thing I haven't seen mentioned anywhere is that the final group of infiltration ships always land in major cities in the area. That's what I found out on my latest round of tests.

 

- Zombie

[Prrsha]

I've discovered something interesting about alien inflitrations. I have two scenerios for an example.

 

#1 In the beginning of a month a wave of 3 ships headed to brazil under a base construction mission. the fleet consisted of 2 battleships and one supply ship. The very second the supply ship entered the south america zone (not just brazil) an alien base appeared right under the nose of my patroling sky ranger (in the center of Brazil). It built at exactly the same area every time with a reload. Once the base was built Brazil flagged as defected. A few mins later 2 battleships appeared but downing the 3 ships over land had no effect.

 

#2 In the middle of the month an alien inflitration fleet headed to India. 4 ships appeared in sequence over a 5 hour peroid in this order: a large scout, a terror ship, a base supply ship and finally a battleship.Dowing all of the ships over land had no effect and India signed a pact with the aliens. I reloaded and an earlier save point a few hours prior and this time the scout appeared over my base in the usa headed to india. I sent a firestorm after it while it was over the water. Meanwhile the terror ship appeared in Africa near one of my bases, I took 3 regular interceptors to intercept it. My firestorm then downed the scout over the ocean right near africa. My 3 interceptors downed the terror ship in the african desert. After that to my shock.... no supply ship arrived or a battleship. India didn't defect.

 

My thoughts are maybe if you down the scout before it flies over land on the target continent... It haults all other ships from appearing like the supply ship. In my experience once the supply ship appears the base is built and the country defects.

 

Another though is that maybe killing the scout and terror ship was enough to hault (and forget) the mission and instead trigger an alien retaliation mission?

[Tycho]

There is no way to completely stop infiltration missions. Once the second battleship has appeared, the pact is signed. Shooting down any of the UFOs will add a huge delay to the time for any subsequent UFO to appear. Once the terror ship has been generated, there is only an hour (average) delay between the supply ship and final two battleships, each. The player would need to have advanced ships very close to the insertion point of the terror or supply ship to intercept them quick enough.

[Prrsha]

I have no idea why the supply ship and battleships didn't show up. The just well... didn't... I had no trouble from the central asia infiltration fleet for over a month except I did notice they attacked my home HQ in rather a short amount of time. India hasn't signed a pact with the aliens in 2 months and counting and no further ships have appeared with the mission listed on their ufos. Also the attempted inflitration happened around the 10th of the month, so I doubt time ran out on their mission.

 

I'm using the fully patched na vanella version. The only thing that was altered is that I used ufoutil to fix the "beginner difficulty" bug but other then that no changes were made.

 

I forgot to add that I am also using the DOS version. Maybe this was just a bug or a fluke of luck? Whatever it was I'm counting my lucky stars! I have the save files if someone wants them for further examination...

[magic9mushroom]

I have no idea why the supply ship and battleships didn't show up. The just well... didn't... I had no trouble from the central asia infiltration fleet for over a month except I did notice they attacked my home HQ in rather a short amount of time. India hasn't signed a pact with the aliens in 2 months and counting and no further ships have appeared with the mission listed on their ufos. Also the attempted inflitration happened around the 10th of the month, so I doubt time ran out on their mission.

 

I'm using the fully patched na vanella version. The only thing that was altered is that I used ufoutil to fix the "beginner difficulty" bug but other then that no changes were made.

 

I forgot to add that I am also using the DOS version. Maybe this was just a bug or a fluke of luck? Whatever it was I'm counting my lucky stars! I have the save files if someone wants them for further examination...

 

Shooting down a UFO on a mission adds a significant time delay before the next UFO in that mission appears. It has no effect on whether it does (eventually) appear, as missions have an exact profile of what ships will appear how many hours after the last ship in that mission appeared. The classic Infiltration and Base fleets appear because these time delays are set to very short intervals (so the later ones in sequence spawn while the earlier ones are still on the globe) - the characteristic "fleets" are Large Scout - Terror ship - Supply ship - Battleship - Battleship for Alien Infiltration and Large Scout - Supply ship - Supply ship - Battleship for Alien Base. If you shoot down some of the components of the fleet before the entire fleet spawns, the time delay will kick in and so the other ones won't spawn until later, but they will all eventually spawn (and at the moment the Battleships appear, bases will spawn on the planet).

 

I suspect you're confusing "supply ship crosses into target zone" with "battleship appears in atmosphere" as the trigger for base construction, and also confusing Alien Base and Alien Infiltration missions (Alien Base missions have only one Battleship, spawn only one base and do not cause infiltration; Alien Infiltration missions have two battleships, cause infiltration, and can spawn two bases - not sure if it's always two but I've definitely seen two show up from an infiltration before). The Hyper-Wave Decoder can tell them apart.

 

IDK what's going on in your game, but I have some suspicions.

 

1) IIRC the country that's infiltrated isn't determined until the time the infiltration succeeds (possibly - this is my supposition - by checking what country the last Battleship's urban target is in, whether or not it actually survives to touch down there). It's possible that the mission did complete without your knowledge (the remainder of the fleet would have been delayed for days or even weeks by your interceptions, and you might have shot them down in completely separate areas of the globe) but the random city target roll selected a city that wasn't inside a funding nation (Baghdad, Tehran or Karachi are the targets I can see that are in Central Asia but not India). Infiltration missions don't end, they repeat; still, it takes at least a month (and possibly two or three if you shot down all the scouts) to get to the "country loss" part again.

 

2) You delayed the infiltration by long enough that it crossed over a month boundary or two and you haven't received the news of the infiltration yet.

 

3) Something glitched in MISSIONS.DAT and made the AI forget that an Alien Infiltration mission was ongoing in Central Asia or made it think the rest of the mission was happening someplace else. Corrupted saves do happen.

 

4) Something I don't understand is going on and I'm just being a pompous twit. Some of this includes data I'm not sure about, so take it with a grain of salt.

 

 

If I'm actually on the money about the infiltrated country being selected by city, this might explain Russia's immunity to infiltration in the Collector's Edition. Russia only has two cities, one of which can't be targetted by an Infiltration mission (Novosibirsk, which is in Siberia - infiltration missions don't happen in Siberia just like they don't happen in Antarctica or the ocean). If Moscow was missed in the "UFO urban target in Europe" list in the CE, that would make it impossible to infiltrate. Has anyone seen a UFO touch down in Moscow in the CE?

[NKF]

I seem to recall a while back while I was digging the appearance ratios out of the .exe that I had a bit of fun and altered the tables so that only one type of alien would appear except for one month where a different race would show up as a control race. Then I did some further .exe editing and souped up the interceptor and cannon to be able to blow up battleships in one shot and then a quick edit of the facil.dat file of the current save to allow for free facility construction and ridiculously impenetrable defences.

 

One of the observations I had was that though you could prolong the mission by shooting down the subsequent ships, there seemed to be a a point where my control race just stopped sending UFOs and were never seen again. Something like a month or two after the first UFO in the chain.

 

I must admit I don't exactly remember what mission type this was for. It was most likely retaliation. Though, could this also be the case for the infiltration missions?

 

- NKF

[magic9mushroom]

I seem to recall a while back while I was digging the appearance ratios out of the .exe that I had a bit of fun and altered the tables so that only one type of alien would appear except for one month where a different race would show up as a control race. Then I did some further .exe editing and souped up the interceptor and cannon to be able to blow up battleships in one shot and then a quick edit of the facil.dat file of the current save to allow for free facility construction and ridiculously impenetrable defences.

 

One of the observations I had was that though you could prolong the mission by shooting down the subsequent ships, there seemed to be a a point where my control race just stopped sending UFOs and were never seen again. Something like a month or two after the first UFO in the chain.

 

I must admit I don't exactly remember what mission type this was for. It was most likely retaliation. Though, could this also be the case for the infiltration missions?

 

- NKF

 

It's possible that there is a time limit on missions, yes. We would need to find the code for it to have positive proof, though.

 

If a time limit does exist and fully ends Infiltration missions, that would make the number of alien bases built finite once infiltration missions had been timed-out in all zones, and make all countries in areas timed-out on their Infiltration mission immune to further subversion. So I doubt the time limit, if it exists, allows you to fully end an Infiltration mission, only restart it.

 

Basically we need more tests. Oh well, I bit the bullet and hex-edited the difficulty bug out of my copy of UFO Defense, so if I'm going to be replaying it anyway I might do some of that once I'm done.

[Bomb Bloke]

One thing that caught my attention, if you've any interest in testing it, is that the files tracking retaliation missions handle only eleven of the fourteen zones available in the world. The North Atlantic, South Atlantic and Indian Ocean (pictured) should each be free from base attacks against XCOM, best I can make out - it shouldn't be hard to plonk a base up top of the North Atlantic, but due to the lack of UFO activity there the little spec of land at the bottom of the South Atlantic would be a better bet.

[NKF]

If a time limit does exist and fully ends Infiltration missions, that would make the number of alien bases built finite once infiltration missions had been timed-out in all zones, and make all countries in areas timed-out on their Infiltration mission immune to further subversion. So I doubt the time limit, if it exists, allows you to fully end an Infiltration mission, only restart it.

 

I don't imagine you would run out as the game can always restart a new lot of aliens on an infiltration mission in the following month. I guess perhaps not the infiltration mission itself, but the current chain of ships and crew type may get reset after a certain time has passed.

 

I suppose it's not something you'd observe in a normal game with its more normal spread of alien types compared to what I had at the time.

 

- NKF

[magic9mushroom]

I don't imagine you would run out as the game can always restart a new lot of aliens on an infiltration mission in the following month. I guess perhaps not the infiltration mission itself, but the current chain of ships and crew type may get reset after a certain time has passed.

 

I suppose it's not something you'd observe in a normal game with its more normal spread of alien types compared to what I had at the time.

 

- NKF

 

This is my understanding of how the alien command-and-control AI works. Correct me if I'm wrong at any point.

 

- At the start of each month:

-- One generic alien mission is generated (potentially more under certain conditions?). One Alien Terror mission is also generated.

-- For each generic alien mission, consult ZONAL.DAT and roll for which area the mission is going to be in.

-- For each alien mission in an area, consult ACTS.DAT for that area and roll for which mission type the mission will be.

-- For each typed alien mission thus generated, zero the respective priority in ACTS.DAT for that mission in that area. If all fields in ACTS.DAT are zeroed for an area, zero the respective priority in ZONAL.DAT for that area.

-- (How are Alien Terror missions localised to an area?)

-- For each typed alien mission (including both those from ZONAL.DAT/ACTS.DAT as well as Alien Terror missions), consult the Alien Appearance Ratios table in GEOSCAPE.EXE and roll for which race will do the mission.

-- Begin the rolled missions, starting clock at month start.

- At the start of each day:

-- For each Alien Base on Earth, roll for whether an Alien Supply mission is generated for that base.

-- For each Alien Supply mission, set the race of the owners of the base as the race which will do the mission.

-- Begin all missions so rolled, starting clock at day start.

- When any activity occurs that provokes Alien Retaliation (I'm not sure exactly which acts run a provocation check?):

-- Roll for whether an Alien Retaliation mission is generated for that area.

-- (Are Alien Retaliations a rolled race or are they locked to the race whom you provoked?)

-- Begin any missions so rolled, starting clock at (presumably either previous half-hour or next half-hour?).

- When a scout on an Alien Retaliation mission finds a base:

-- Add that base to AKNOW.DAT.

- At some time I don't know:

-- For each X-Com Base in AKNOW.DAT, roll for whether a Battleship is sent to destroy that base (second half of Alien Retaliation mission).

-- Begin any "missions" so rolled.

- When a Base Defense mission is forced:

-- Remove that base from AKNOW.DAT.

 

This would seem to indicate that once an Alien Harvest (for instance) mission has occurred in, say, Europe, there will never be another Alien Harvest mission in Europe. Thus, if Alien Infiltration missions didn't have the attribute of looping upon completion, only one country could be infiltrated per area.

 

Just confirmed that the ACTS.DAT value for a given combination of mission and area is indeed zeroed upon mission start (excepting the Alien Research mission that's always started in the player's home zone) and doesn't return upon mission end, which would seem to confirm that each available act is only performed once in each area (this still leaves several years of game time before all acts are exhausted). I guess the way to completely confirm this is to run a game into/past March 2003 and see whether the aliens are still doing anything besides Infiltration, Terror, Supply, and Retaliation (by March 2003 at one mission per month the aliens will have completed all 49 missions available plus the Alien Research mission in January 1999 that doesn't come from ACTS.DAT; as such the only remaining alien activity should be that that doesn't rely on ACTS.DAT to trigger it). And then you'd check whether all the Infiltration missions were still running or whether you could snuff them out by then. Something like that.

[Tycho]

You can delay the final result of an infiltration by intercepting the scouts but you can never stop the infiltration from succeeding. Unless, the game glitches and corrupts the MISSION.DAT file in some way. Infiltration succeeds after the last UFO in the mission has spawned. The only country that can't be infiltrated is Russia because the infiltration chance for the Siberian zone was set at zero. There is no final time limit. I have seen a game where every country has signed a pact but the game continues, since the economic model is hopelessly broken.

[magic9mushroom]

You can delay the final result of an infiltration by intercepting the scouts but you can never stop the infiltration from succeeding. Unless, the game glitches and corrupts the MISSION.DAT file in some way. Infiltration succeeds after the last UFO in the mission has spawned. The only country that can't be infiltrated is Russia because the infiltration chance for the Siberian zone was set at zero. There is no final time limit. I have seen a game where every country has signed a pact but the game continues, since the economic model is hopelessly broken.

 

I've heard Russia can be infiltrated in DOS versions.

[Tycho]

I've heard Russia can be infiltrated in DOS versions.

 

I just checked the DOS Geoscape.exe (1.4 and 1.2) and the entries for Russia are zero there, as well.

[magic9mushroom]

I just checked the DOS Geoscape.exe (1.4 and 1.2) and the entries for Russia are zero there, as well.

 

I'm sure the entries for Siberia are indeed zero (I've checked them myself), but Russia doesn't consist wholly of Siberia; Moscow is in the Europe zone, whose Alien Infiltration entry in ACTS.DAT is not zero.

 

Oh, well. I'm doing a Superhuman ironman run at the moment anyway. Once I'm far enough along I should be able to test it myself.

 

But yeah I've seen people say "Russia got infiltrated in my game", and if that's true then all theoretical allegations of its invulnerability are obviously wrong.

[Tycho]

Looking at the code for how alien infiltration success works, Russia is the sole country in the Siberia zone.

[magic9mushroom]

Looking at the code for how alien infiltration success works, Russia is the sole country in the Siberia zone.

 

Earlier in this thread:

 

I can testify that Russia (and every other damn country) can be infiltrated, I'm sure others can testify to this.

 

If your hypothesis says it's impossible, and it's recorded to occur, your hypothesis is wrong. No amount of theorising can overrule the data.

 

I know there aren't any countries other than Russia in the Siberia zone, the question is whether Russia is also in the Europe zone.

[Tycho]

If your hypothesis says it's impossible, and it's recorded to occur, your hypothesis is wrong. No amount of theorising can overrule the data.

 

I know there aren't any countries other than Russia in the Siberia zone, the question is whether Russia is also in the Europe zone.

 

In the CE code, as regarding infiltration success, Europe zone is composed of UK, Germany, France, Italy, and Spain. When the Europe zone infiltration mission has succeeded, only one of those countries will be signed. The order is specific as well. Russia is not in that list.

I was not giving you a hypothesis. I'm stating how the code in those specific areas is written. By the code, Russia can only be successfully infiltrated if the Siberia zone has been chosen for an infiltration mission, which can't occur as the chance for that is zero.

I have a saved game that was given to me by another player for the CE version. At the time of the save, the game time is Aug, 2002. Russia is the only country still active. All the zones in ZONAL.DAT are zero so no other missions, besides base supply and retaliation, can occur.

 

The hypothesis is: There is something different in the DOS version that allows Russia to be infiltrated.

[magic9mushroom]

The hypothesis is: There is something different in the DOS version that allows Russia to be infiltrated.

 

So why are you saying Russia can't be infiltrated in the DOS version?

 

As I said, though, I plan to test this myself.

[NKF]

It sounds a bit like the old Tasoth Commander myth from TFTD. Some of us seem to have memories of it in the old dos-era days, but it is proving very difficult to verify.

 

Incidentally, someone mentioned Novosibirsk a few days ago, perhaps in another thread. Once upon a time, I thought that city was always the first to get a Terror mission in every game I started. Well, for a while at least. No, no, not much relevance to the infiltration theme here, but thought I'd mentioned it before it slipped my mind.

 

- NKF

[Bomb Bloke]

There's also the possibility of people confusing "pact signing" with "infiltration".

[Tycho]

I'm curious about the results of the game. As much as I have been able to decipher from the hex codes in the DOS Geoscape.exe, the logic to the routine for infiltration success is exactly the same as in the Windows version: Russia is in the Siberia zone with no links to any other zones.

 

There is confusion over Russia in the game: for infiltration purposes, Russia is considered in Siberia but when selecting a site for a base, most of Western Russia is classified as Europe.