Known Bugs

The Blaster Bomb Bug - CE

On the Gold/Collector's Edition of X-COM, you had to be damn careful - why? Because, for some reason, Blaster Bombs refuse to travel directly upwards. They don't mind moving diagonally upwards, but they -hate- moving straight up. The aliens are also unaware of this bug and can accidentally nuke themselves. So, with this in mind, you can now avoid blowing yourself up with blaster bombs! :)

This is also true for BBs moving straight down as well! --Danial 20:48, 4 Oct 2005 (PDT)

80-item Limit

When loading up your Avenger for a massive UFO assault or arming soldiers for a Base Defense from your overflowing stores, you will likely hit this limit.

You only get a max of 80 items, and you don't get to choose which ones, so you may end up with 80 clips and no rifles for the base defense, or may not be able to get your hands on that dropped blaster launcher during the UFO assault.

The solution? Timely housekeeping. Sell off your spare personal equipment. See our handy Spring Cleaning Tips, and also Managing the Item Limit for ideas on stocking Skyrangers.

The trouble with Mines (general)

The armed states for Proximity Grenades in both UFO and TFTD are NOT stored in savegames. More information to come.

TFTD Research Tree Bug Avoidance Guide

TFTD's research problems are more of a serious oversight than a true bug. More of a pain, really. Nevertheless, a variation of NKF's TFTD Research Tree Bug Avoidance Guide, coming soon - free time permitting.

Jasonred: I'd say it CAN easily become a true bug. Tech items can literally become impossible to access and will never appear in your campaign. In some cases, making it impossible to complete the game.

For now:

• NEVER research the Tasoth Commander. There's no reason to, as far as I can tell.
• ONLY research Deep One Terrorist AFTER you have completed Plastic Aqua Armor and Ion Beam Accelerators.
• DO NOT research M.C. Lab unless you have AT LEAST one MC Reader in storage.
• You MUST have at least one "Sub Construction" in storage before completing research on Zrbite and/or Transmission Resolver.

Other than the MC reader one, any of the above would make it impossible to finish the game.

-compiled from NKF's guide.

Mountain Map

Due to a bug in the way this tileset was created, when you shoot the ground, it doesn't burn up - it turns into a tree stump.

Because the stump is on object, as opposed to actual ground, any objects that were in the tile already (for example, UFO hulls or the landing gear of your craft) get replaced by these stumps, making it seem as if they were destroyed.

Tree stumps don't take much damage, so they often get burnt up immediately if an explosive goes off, leaving nothing but burnt ground behind. It is easier to view the effects of this bug by shooting the ground instead.

Base Disjoint Bug

Base facilities built along the right or bottom edges of the base building area may end up being cut off from each other by dirt walls, a bug in the routine meant to keep soldiers from accidentally exiting the map edges during Base Defense missions. The dirt walls can be knocked down by Blaster Bombs during combat but are otherwise unbreakable.

NKF illustrates this in a pretty picture for you. XCOMUTIL corrects this problem.

Green Text Bug

There are a few bugs in XCOM, especially early versions, that can build up and make the game unstable enough that it crashes and prints out a screenful of green 40-column text, essentially debug or memory dump information useless to you.

One fairly consistent cause is saving the geoscape game during a UFO standoff, with the interceptor window minimized to an icon. The next mission after that point will likely dump you to the green text screen, and perhaps an earlier battlescape mission instead of the proper one.

-- I was able to recover from this state by quickly sending in another interceptor (Firestorm) to take over, which allowed my first interceptor (Avenger) to break off and go home without crashing the game again. After the shootdown I overwrote the buggy savegame. --JellyfishGreen 03:11, 22 Aug 2005 (PDT)

Interceptions: Using Cautious Attack

When intercepting UFO's, the longest ranged weapon will fire as soon as you are within range of that particular UFO using any attack of your choosing, which is normal. If you use only "Cautious Attack", the craft will only get within range of its longest ranged weapon. Now, if you only have one type of weapon mounted (eg: two Fusion Ball Launchers mounted on a Firestorm), when those weapons have used up their ammo, the intercepting craft will drop back to "Standoff" range. It does this as soon as the last shot leaves the weapon tube. What then happens is that the fusion ball is still travelling towards the UFO which was just in range, but the range counter for the weapon is no longer within range of the UFO (becasue the intercepting craft went to Standoff range, remember!). When the fusion ball (or which ever missile weapon you have mounted) reaches this range counter, it self-destructs.

This means, the last shot of ammo from any weapon using a Cautious Attack will NEVER reach the UFO.

To get around this waste of ammo, click quickly, and alternatively, the "Agressive" button then "Cautious" button so that the UFO stays within this range counter until the weapon has reached the UFO.

Transfer Limit cash eater

Only 100 items can be in transit at a time. (Here, a transfer of e.g. 200 Elerium counts as one "item". Also, all soldiers are counted individually.) If you go over the limit, you will get a warning that there is no more transport capacity. If you STILL try to transport something after getting the warning, the item will stay where it is, but the transportation cost still gets deducted. Bad if you're shuffling expensive aircraft.

Carrying Unconscious Aliens

A critical bug which can crash the game.

If your Soldier is carrying an unconcious lifeform (ie: a Soldier or an Alien), and the lifeform wakes up. They appear in the tactical area. At the same time the image of that lifeform is still shown in the Solder's hand. If you click on that image in the hands, (such as to throw the unconscious lifeform) the game will crash with either a crash to desktop, if using a Windows version, or the possible "Green Text" bug if using the DOS Version (see above for the description). To avoid this bug, go to the soldier equip screen, and place something in the soldiers hand. This will clear the error.

MAYBE DELTETE Below - your call NKF

HEY NKF, ive edited good, do you want to incorporate your info to the above "Green Text" bug.

[ NKF: This works with all unconscious units - not just the aliens. In the dos version, the text that you see is simply a memory dump in mode-13h (the 320x200x256 colour screen resoulution the game uses) and the text colour is based off the changes to the pallete that the game made. The game sometimes continues with the next part of the game. The game is made of two different programs, one for each segment of the game, so when one part of it crashes, the other one will not have registered that anything has gone wrong and will attempt to soldier on.

In the Windows version of the game, the game simply crashes back to the desktop, unless you're using the Xcomutil split executable variant).

Come to think of it, this bug was mentioned elsewhere, but it was tucked away deep in some other section. See: Unconscious. There's a note right at the bottom of the Recovery section. It might need to stand out a bit more. Hmm.]

MAYBE DELETE Above

Disappearing Ammo

If you end a Battlescape mission with weapons loaded with ammo, the ammo will disappear. To prevent this, unload all weapons before ending the mission.