Talk:Known Bugs

did anyone find ANNOYING! the airbourne intercept window of TFTD when flying over water?

Annoying:

Intercept a USO over land then follow it and it may (should) fly out towards to water. The aliens don't usually go straight into the drink so the "Unable to continue pursuit while airbourne" window comes when flying over water "return to base" OR "continue pursuit" as the options. If you'd press the 'continue pursuit', it would just display the window again. The only way to continue pursuit was to click it maybe 10 or 20 times before the aliens submerged. This is nuts! Are there any work-arounds to this than just pressing the "return to base" button?

just checking up ?

Difficulty Bug

We should for historical reasons outline the "Difficulty Bug" that XcomUtil has saved most of us from. Any takers? --JellyfishGreen

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That would only require two or three short lines. Something like this:

" Because of one or two incorrectly set bytes in all dos versions of the game( 1.0 through to 1.4), no matter what difficulty was selected, the difficulty bug would reset to beginner at the end of the first mission. XcomUtil performs a very minor tweak that corrects this problem. This bug was officially fixed in the Collectors Edition Windows port (also commonly known as UFO Gold). "

Or perhaps something a bit more succinct, and with less commas. Ha!

- NKF

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This is a technical bug that doesn't happen to everyone and one this article wasn't really meant to chronical - but we won't turn away helping a fellow player if it can't be helped. It's just that there are so many random crash points in this game that it would take far too long to find them all or come up with solutions for them.

Certainly, the transfer crash can happen to some players, but it's not one that can be reproduced easily. It's just like the random crash that some players get when they research a floater medic. It crashes the game for some of us, but others don't seem to notice it at all.

It really depends on your hardware and OS setup, whether or not your copy of the game is damaged or your savegame is damaged, etc.

Does it happen in all games or just this one savegame?

- NKF

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"Invisible Muton" bug

Upon shooting repeatedly a Muton, it sometimes plays its "death" animation without sound (as if falling unconscious) and it is no longer displayed in the screen, while remaining visible to my soldiers (I can center the screen and the cursor appears yellow over them). Under this state, they cannot be targeted by Stun Rods. They may play their death animation anytime they get shot, until they truly die, when they emit their characteristic sound and leave a corpse (along with any items carried).

I'm quite fond of laser weapons, maybe this happens more often with those.

Also, though I remember experiencing this quite often fighting Mutons, it may happen to any other high health race.--Trotsky 02:59, 2 July 2006 (PDT)

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Never seen that one myself. Another "unpatched game" thing maybe?

There's a (very rare) bug that allows your soldiers to live if they become stunned by an explosion that happens to kill them. Sometimes the game will register their death, and THEN register that they've been stunned. In every case I've seen this happen, however, the unit will have such a low amount of health that a single fatal wound will render it dead (again) on the next turn. I have a vague memory that other players may have been able to get a medkit to the scene on time...

I dunno if that's related to your issue at all (I doubt it, but... meh). I'd advise using a Mind Probe on the alien the next time it happens so you can check the aliens stun/health levels.

- Bomb Bloke

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I'm pretty sure I've seen this with Mutons. Possibly Chrysallids as well, another high health, high armor creature. They were still readily killed by shooting the place they are. Good thought on the MP, BB

---MikeTheRed 08:51, 2 July 2006 (PDT)

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I've been known to have a dying muton(in fire) to spin around and then switch to the female civilian death animation. With the scream and everything. Even got a civilian death registered at the end of the mission. And this didn't just happen once, but on another separate occasion.

Unusually enough, I once had a sectopod die and then drop a tank corpse. I was using the Lightning at the time for my troop carrier, so you can imagine my surprise.

Then there was one occasion where a floater dropped a snakeman corpse. Let's not even get into the sort of things the aliens like to stuff themselves with.

Your invisible alien bug is quite common, although there appears to be many causes for it. I think one involves a full object table when it comes to invisible aliens in bases. But it can also happen in ordinary missions as well. I'm guessing the game may have tried to do something in the wrong order, and sprite information for the unit may have been lost or corrupted along the way.

Having had an experience where all the chryssalids become invisible in one base defence mission was quite a shocker. I fixed this by saving the game, quitting and then restarting the game. If you ever get an invisible alien again, try this and see if it helps. If it doesn't, well, just keep a careful watch on your map and any alerts that pop up as you play.

There's a similar but less severe bug where a dead alien will still leave its centre-on-unit alert button, but this goes away shortly after you move or turn.

- NKF

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That last bug happens when exploding Cyberdiscs kill nearby Sectoids, doesn't it?--Trotsky 23:56, 2 July 2006 (PDT)

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This is a pretty easy one. I guess this bug occured on UFO recovery on a battleship, an alien base assault or a base defense mission? As soon as there are too many items on the map, the game saves some item slots for the equipment to be displayed (since it is more valuable and more important to research). This would also make stun weapons lethal if the stunned aliens would vanish. therefore the game has a failsafe if an alien is stunned (or badly wounded and becoming uncontious). The downed alien's stun level is set exactly on its left health points therefore resurrecting it instantly. This cycle is broken when the alien is finally killed. This means if you want to stun an alien in such a situation you have to destroy some items first.

- by tequilachef (April 4th 2007)

Vanishing snakemen

I've known snakemen to become invisible when standing on a hay bale. On the first occassion I had a poor tank getting shot while spending numerous turns looking for it. On the second occasion I had an alien under Psi-control, left it on the hay bale, and couldn't find it next turn. - Egor

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This is not limited to snakemen. Hay bale block visibility quite much when a unit is standing on it. Two possible solutions: - Destroy the hay before entering - Shoot at the hay. If it is destroyed any unit on it will become visible (as long as no other bales are blocking the line of sight). You might also hit the enemy directly.

I Dnt know if the aliens are affected by this diminished sight, too. My guess would be no.

- By tequilachef (April 4th, 2007)

Blaster Bomb Bug

I'm currently playing through X-com UFO Defense, I have the collectors edition version. I'm in the process of trying to catch a live alien commander and the blaster bomb bug is making this very difficult. If i remember correctly a commander is always in the command center of the the alien bases. The problem is anytime i get close there is always a dude with a blaster launcher up there that tries to kill my troops. When they try to fire it down at me the bug kicks in and they blow up the whole command room and all the aliens in it because they can't figure out how to get the blaster bomb down the grav lift thing in there. This is making it very dificult to actually catch a live commander. Anyone have any ideas for tactics or anything to breach that room without the aliens trying to fire a blaster launcher up there? - eL Hector

I can suggest two possible solutions. The first is to wait outside the command room for the alien to move closer to you. If it comes out of the room or if you know it has moved down the lift, you then burst in and stand right next to it to stop it from firing the blaster. This is risky because there could very well be a heavy plasma toting alien in there. The other is to use a small launcher and launch it up at the ceiling near where you think the alien with the blaster is standing. -NKF

Disappearing Ammunition

I have observed that problem with X-COM 1.2, modded with XCOMUTIL. My stun bombs and heavy rocket missiles, along with clips for the auto cannon went missing. Vagabond

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Just run a test using my 1.4 DOS version with XComUtil but my stun bombs didn't disappear: 30 + 1 back in the base they came from, same number after I went tactical and I dusted-off immediately. Are you running XComUtil with Runxcom.bat or did you simply run Xcusetup?

Hobbes 22:12, 22 February 2007 (PST)

Is it a case of hitting the 80-item limit?--Ethereal Cereal 12:28, 23 February 2007 (PST)

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With runxcomw.bat, as everytime. Apologies, I retested and it seems like I was mistakened, but I could have sworn that I lost them dang stunbombs. Had to manufacture some. I will test some more, using four heavy weapons and seeing whether their ammunition disappears at all. Thanks. Vagabond

MC at end = MIA?

I am sure I have seen this again recently, where I won a mission with no casualties (I thought), but the last thing I killed was a Commander that had been chain MC'ing a psi-attack-magnet trooper, and that trooper was listed as MIA at the end (presumably because he was on the enemy side at the end of combat). Is this a bug, or is there another way to get MIA's on a completed mission that I might have missed?

Since then I have been waiting for the leaders to panic at the end before killing them (or waiting for a rare resist), so I can safely exit, but am I being overcautious?

--Sfnhltb 13:45, 27 February 2007 (PST)

If the trooper was mind controlled on the turn you killed the last alien it will be listed as MIA. No bug there :)

Hobbes 18:16, 1 March 2007 (PST)

Huh, why would that happen - your soldier should recover the very next round, why would he go MIA?

--Sfnhltb 18:20, 1 March 2007 (PST)

Doesn't make sense to me as well but that's how the game works.

Hobbes 15:05, 2 March 2007 (PST)

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It seems that regaining control of units under enemy mind control works different for alien and human players. My guess: aliens under human MC are reverted to alien control AFTER THE ALIEN AND BEFORE THE HUMAN TURN while human units under alien control are reverted RIGHT AT THE BEGINNING OF THE HUMAN TURN. This explains three different phenomenons:

- The discussed MIA "bug" (he unit would be returned in the next human turn, but since it never starts it is lost. The mission is still won since no unit with a "genuine alien" marking is left)

- The fact that a mission is lost when the last human falls under MC while it is not won when this happens to the last standing alien (the aliens get their unit back before their turn starts and therefore have a unit left to pass the "anyone alive?" check, the humans would have no unit left to start a turn with. They WOULD have as soon as the turn starts, but no unit left before turn means bust)

- The fact that aliens still can see all an MCed human saw at the end of the human turn that follows the MC while this is not vice versa (The MCed human can give information to the alien side before reverted while an MCed alien is reverted too early). The result is that aliens can control a human indefinitely without having any alien seeing him until the MC is disrupted for one turn.

All confused? Then I did a good job! No seriously, this must be the explanation, I couldn't think of any other way.

- By tequilachef (April 4th, 2007)

You're absolutely correct on the first two points. It's a sequence issue - you never get round to recovering the unit before the new turn starts, so you end without any units whatsoever. Makes senses too since the aliens would continue to continue to mind control that same unit over and over indefinitely.

The third point however: The aliens don't need to know the location of the last MC'd unit. They know the location of all your troops whether they've seen them or not from the very start. They appear to give you a few turns of grace where they won't attack you outright (unless, from my observation, all your soldiers are incredibly weak). This is evident because all of the aliens will eventually make their way towards the nearest soldier even though their movement pattern may seem semi-random. Also, they know where you are because they can initiate psionic attacks without having seen any of your troops. They generally go after the weakest troops first.

Just to add a semi-related point, but from the alien's perspective. If an MC'd alien unit is in the exits when you abort the mission, this alien is not recovered and in fact simply vanishes. Any equipment it was carrying is recovered, unknown artefacts or otherwise. You could possibly think of this as their version of MIA. However, the aliens differ ever so slightly in that if it's the last alien standing and under temporary mind control by the player, the mission doesn't end straight away. But I guess this is only because the player has everything under control, whereas in the other scenario, the Ai is in control.

-NKF

Crash Site in the atlantic ocean

That's right, my game generated a crash site on water. Here are the details:

- Crash Site a bit southeast of the USA (which was infiltrated a few days before by sectoids, resulting base had already been taken out), but certainly not on land.

- UFO: battleship, floater, alien harvest

- Geoscape: 8 X-Com Bases, 1 (known) Alien base, 2 other crash sites, 1 other (known) flying UFO (though almost worldwide decoder coverage), 3 X-Com Crafts out, 1 waypoint

- Date: January 2000

- Most Interesting: The Craft that downed the ship was a recently finished Firestorm (first human-alien hybrid craft I had built, I know this is lame for that date. Limited myself on 25 Scientists to improve the challenge) equipped with twin plasma. I had it built and equipped in Antarctica and then transferred to Europe. This base had no Elerium, a fact that enabled me to use the infinite fuel exploit which was in effect when downing the UFO. My craft was only slightly damaged when doing so. The battleship was the first target assigned to the craft, it came directly from my base.

- When shot down, the UFO was not targetted by any other craft.

- I had not lost or sold a single craft to that point.

- When sending a squad to the crash site the game didn't crash but generated a farm land ground combat terrain.

- I was not able to reproduce the bug from the savegame dated 2 hours before downing the UFO

Well guys, any intelligent guesses? I still have the savegames (before and after downing)! If you want to have a look, write here.

- By tequilachef (April 5th 2007)

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Well I'm sure you know about crash sites that are near land can sometimes actually be on water, so I'm going to assume that this site is well far away from any land mass. Could it be a weird entry in GEODATA\WORLD.DAT that has a land mass out in the ocean? Also are you sure the game didn't crash? Sometimes when it does it will load the previous mission (and usually 90% are at farm terrain). Are you sure it generated a new map and not load the last one?

No real guesses but maybe some starting points to look at. I've probably stated some obvious situations you know about and have accounted for, but it never hurts to double check :D

- Pi Masta 14:23, 5 April 2007 (PDT)

Inconsitencies in MCing Cyberdiscs and Sectopods

I experienced, that when MCing one quadrant of a large terror unit any action it does only affects this quadrant (especially use of time units). That means, when TUs are up for one part, MC another one and continue firing. This however does not work out when moving the unit while it is not under complete control. The TUs used up by the resulting reaction fire from the rest of the unit is also deducted from the TUs "your" part has left (making it impossible for the controlled parts to return fire). This however only happens under reaction fire, not if "your" part fires on it's own. I don't know if this comes up when uncontrolled parts shoot by themselves in the alien turn, since this is hard to find out.

That's because large units literally are made up of four separate units. They only share the same set of general stats (in unitref.dat). Unfortunately the 'under mind control flag' is unique to the four units, not the shared stats! So you in effect have multiple units under different control sharing the same stats. So if you move and it results in a reaction from the unit, it will spend the TUs you're using.

Successful mind control automatically fills up the unit's TUs, so each mind controlled sector gets to move or attack again until there are no more sectors to mind control. Useful way of turning reapers into long range scouts!

In TFTD, they attempted to fix this bug, but in fact made it much-much worse! The only way to mind control the unit properly is to control the upper left quadrant. Only! Any other quadrant will result in a partial (clockwise) control, and you may gain control of units other than that unit, or may even get into situations where you gain permanent 'partial control' of a large unit you haven't even sited. Wackiness all around!

- NKF