This is a great game, but it's full of bugs and possibilities to cheat as Swiss cheese is full of holes. However, you can easily win WITHOUT cheating at all if you act upon the following advice:

1. NEVER USE TANKS! They're too expensive to lose. You can't throw a smoke grenade outside on a first turn, thus losing the element of surprise. Four soldiers are definitely more effective, both in terms of arm power and maneuverability.
2. Use laser pistols. They're lighter, faster, effective, need no ammo, and are easy to handle.
3. Use rocket launchers with small missiles (as many of them as your people can carry (at least two of them per launcher, and ten per mission at a minimum)).
4. Every soldier should have at least one proximity grenade and one regular grenade (preferably two). Your team should also have at least five smoke grenades.
5. Use rocket launchers to destroy enemies at a distance, to clear your way to your troopers, and to destroy house walls. Never walk into a house, but destroy the wall with a rocket from a distance to see what's inside, and then kill anybody inside.
6. Use hand grenades (with the time set to zero) to kill anything...
   1. in the woods
   2. behind the tall bush fence
   3. on the other side of houses
   4. in a passage between two small houses that you can't shoot immediately with a rocket
   
   
   If you have the protection suit and enter into a close encounter with an alien, but have no time to do anything else, simply drop the bomb on the floor (it'll kill him, but not you).
7. ALWAYS throw a proximity grenade in front of a ship's entrance and wait at a distance. If there're any aliens inside, they'll eventually come out and step on it. Sometimes it may take several turns for them to make their minds up about going out, but they will. If any aliens survive, shoot them (use a rocket if you need to), and then throw another proximity grenade on the same spot.
8. NEVER go inside a ship, unless it's a terror ship, since it contains aliens on the upper floor that can't go outside by themselves (reapers, cyberdiscs, or sectopods), or unless you're using a brainwashed (controlled) enemy soldier.
9. Use small launchers for capturing enemies.
10. Enemies won't move if none of them saw you and stayed alive at the end of turn. Therefore before leaving your ship, throw a smoke grenade just outside of it. At first turn, don't go outside, instead prepare your grenades (take two turns if necessary). If you see an alien that doesn't see you, throw a grenade at him, don't shoot him, since you may miss, and he may remain alive and retaliate and you'll loose the effect of surprise.
11. Take care to maintain some distance between your people (if one of them dies, why should they all do so in a chain reaction of prepared grenades).
12. Landing on a proximity grenade from above (with flying suit) won't activate the device, so you may lift it (or any other item), and evacuate the area.
13. Have two or three medikits, just in case.
14. When attacking a base, prepare your grenades; move slowly and carefully; throw a proximity grenade in front of every door that leads to a guard post (do it in stealth mode as you shouldn't be seen while doing this). When there's finally an alert, they should all die at once by stepping on your traps.
    
    Leave someone at key positions to control the passages to guard posts. When you're on Mayor Base Center, throw proximity grenades in front of the main door (the outside one), and through the small windows if possible. Cover your movement in the open parts by using smoke grenades. If you have at least ten psi-amps, the soldiers equipped with them should be somewhere behind and lightly armed, so they can use the psi-amps twice. It's relay easy with them. Have three mind probe equipped soldiers (so that you can inspect six aliens in a turn if necessary). Don't attack a base, unless you have an Avenger (you'll need a lot of soldiers if you wish everything to go neatly).
    
    Use blaster launchers if necessary. If you're using them while attacking a race that has mind powers (ethereals or sectoids) never finish a turn with them in your soldiers' hands (drop them on the floor), since they might be used against you. The same warning applies to heavy plasma rifles. Use flying suits if available.
    
    
15. When you're defending a base, there's a bug and a way to fix it. If you have more then eighty-one items in a base, and you see an enemy ship that's approaching to attack, transfer all unwanted equipment somewhere else, or put the excess items in a craft and launch it, so that only eighty-one items remain. You'll then be able to assign them all to your troops, and equip them properly according to your wishes. Otherwise the computer will allot the first eighty-one items from the stores to your team. You may end up with useless junk instead of arms.
16. If you've successfully achieved a mind control of your enemy, you can manipulate the items that he caries by using the "list persons" menu. Drop all dangerous weapons that he's carrying, and use him afterwards as a scout. If he discovers someone else, he'll be shot at, and you'll gain another opportunity to take control of another alien (or you may just shoot him).
17. Never use motion scanners. They're useless if you never go inside a ship or house (and you don't and should not have to).
18. If you're attacking a battleship (in the air), wait in standby mode until all gather at the target. Then use four crafts if possible (equipped with plasma cannons, or Firestorms, or Avengers.
19. Make your bases near the places that you wish to defend (somewhere in west Europe, Chicago in America, or Shanghai in China, are good locations), or in clear deserted places that are easy to defend (sweep operations on North and South poles are really nice to play). The poles are also good places for your bases, since traveling from Europe to America (or to Asia) is much faster if you go across the pole instead going around.
20. Build a hyperwave decoder as soon as possible. Build two on different sides of a globe to cover all of the alien activity.
21. Radar systems, defense systems and shields are just a waste of money, since you can outfight the aliens anyway if they dare to land near your base.
22. When constructing a base bear in mind that you well might have to defend it against intrusion, so build your hangars grouped on one side so that in case of attack you can throw proximity grenades at their entrances. Blaster bombs are also very good for clearing a hangar. Wait for your enemy to come for you, don't run to him.
23. Use avalanche missiles for crafts,and switch to plasma cannons as soon as possible (you'll save valuable storage space). If you have fewer cannons then crafts, put one of them on each craft instead of two. Build Firestorms for speed, Lightnings for speed, fighting, and sweep missions, Avengers when you have a lot of everything for base assaults and the ultimate attack on Mars.
24. You'll be able to use alien weapons even though you did not collect the technology from them, however you'll have to research the alien weapons technology. Same for UFO construction. You'll have access to researching all available (or most) UFO ships and Alien life forms, including researching the cyclona bust (or whatever) which will enable you to go to Mars and destroy the alien base. Only an avenger can fly to Mars... and equip your players with fusion ball launchers and the most destructive weapons available for Mars. A Formidable ship is the Avenger with Fusion ball launcher and Ammo!
25. One hundred engineers is enough (you'll need three workshops). All engineers should work together at one base. Put all of your scientists in the other one (one to two hundred (i.e. about one hundred fifty) should be adequate.
26. When assigning scientists to a project, first assign all the available ones, and then when you see some progress, remove the unnecessary ones to a new project. If your progress is "average" with, say, forty-seven scientists, and goes to "good" at eighty-five,it completely *doesn't matter* whether you assign 47, or 84 scientists, it'll still be finished at the same time. It's more efficient to work on several projects at an average rate of progress, then on one with an excellent rate. However, sometimes you may get an instant discovery if you assign an enormous number of scientists to a project that's already progressing at a "good" rate.
27. Never remove all the scientists from a project that's already started, or you'll loose all the information about it that's already been gathered.
28. Before questioning a captured leader, first research mind probe, and alien origins, or you'll later have to capture another one for questioning.
29. A mind controlled cyberdisc can successfully shoot himself. So can a Sectopod. Cryssalids are very stupid and therefore hard to control (unless your soldiers are really experts at mind control), but they can be great scouts, since they have a lot of movement points. Mutons are very hard to kill anyhow, but they're easily mind controllable. Use blasters on them if you don't have psi abilities. Use regular grenades on Sectoids, alien grenades on floaters and snakemen (you can use regular ones too, but the effect is uncertain), and proximity grenades on all of them. Use your brains against Ethereals (psi abilities).
30. If you don't equip your soldiers with armor, they'll die more easily, but will be cheaper to replace, especially if they're using only conventional weapons. However, it's very wise to arm and protect heavily the first four or six in the craft, since they're the most probable targets, and if killed at the craft entrance during first turn, may actually cause a chain reaction of prepared grenades that'll instantly wipe out all of your crew. The cure for that is to give them rocket launchers and to tell the first two to only prepare smoke grenades. Later they can switch to laser pistols or other grenades if necessary (when their deaths won't endanger the rest of the crew).
31. Soldiers equipped with mind probes should not leave the craft in the first place, since they can do their duty from there successfully.
32. If your engineers are lying idle, tell them to build motion scanners. This is the ONLY profitable item for production, assuming that you pay the working force at the end of a month. If you don't, then this is the most profitable one.
33. If you're still having trouble, try playing something less complicated (like `Space Invaders') ;->

Mind controlled aliens can't be stunned (if you do stun them, they won't be captured, since they haven't been enemies since the moment they lost consciousness.

Don't save your game while in tactical mode. If you do, when you reload it, all your previously activated proximity grenades will become duds and fail to activate when someone steps nearby. I think they'll remain duds in a next mission too, so if you really must save a tactical game, sell all your grenades after a battle is over and buy new ones.

If a stunned soldier dies from a reason other then old wounds (usually as the result of a nearby explosion), he won't be counted as "missing in action", nor as "killed in combat", so you won't get negative points. You don't really need a cure for that.

Soldiers assigned to psi training, must be in a base in which they're assigned for training at the end of a month, or they won't learn anything at all.

If you have two bases, transfer a craft from one base to another. When it arrives, you can send it to a mission and it will have an unlimited amount of fuel (In fact, it'll continue to fly after running out of fuel). Your craft should be completely equipped and ready before transferring to perform this trick.

Personnel and crafts are getting their salaries at their home bases. If they're in a middle of a transfer between two bases at the end of a month, then they don't really have a home base of their own, so they won't get paid. You'll save *a lot* of money, and they won't even complain when they arrive. Take care not to transfer soldiers that you have assigned to a psi-lab facility, since they won't get their training either, and I think that you don't wish for that to happen.

After playing the game for a while and building up your stores save the game. Now quit the game and go into your current save game directory and make a copy of the base.dat file. Now boot the game back up and sell everything you have (if you need money) or transfer stores (not ships or personnel) to other bases. Now save the game again and quit. Next replace the base.dat file with a the copy of the original that you made earlier. Now when you return to the game you'll have all the money from the sales plus all the equipment you sold, and if you transferred anything, those items will arrive shortly. Continue the above procedure as often as you like.

How to create an item without expending any money: Click on the item you want on the "Manufacture" screen. Leave the number of items and engineers at zero and click on "OK". Now select it from the list of production items, allocate the number of engineers, but only produce one item. You'll find that you've created the item without cost to you.

It's possible to generate considerable working capital over time by allocation of production to equipment that doesn't require existing stock of special items (e.g. laser weapons that only require money) on the "Sell/Sack" items screen. See the following example:

Regarding the above, it's been noted by John Smith that "It is a little bit bogus, since you will have to pay your working force at the end of a month as well, and thus you will end up loosing your money unless you are producing motion scanners. They are the only profitable item for production."

If you can continue to shoot down an adequate number of UFO's and have a sufficient supply of engineers, it is possible to accelerate the rate at which you can generate money. Using the above noted method, first get more engineers. Use some of these additional engineers to populate bases that are devoted solely to generating extra money. Use the rest to generate the weapons that you require.

This one requires a little file editing and may require some file renaming. Edit the file: liglob.data in the save game directory. Insert two dollar signs ($$) as the first two characters of the file and save it. Now load the game normally. This modification may cause your computer to crash when the reaper moves on a ground assault. If this occurs, delete the files: X_REAP.PAK (reaper character definition) and X_REAPANIM.PAK (reaper animation) from the units directory. Copy MUTON.PAK and MUTONANIM.PAK to some other directory (in RAM: for example and rename them to X_REAP.PAK and X_REAPANIM.PAK respectively. Now move them back to the units directory. Now when you see the reaper move, it won't crash the game. Of course it won't look like the reaper either, but the game won't crash.

In order for this cheat to work, you must FIRST construct all 3 bases on earth. Try to spread them out wisely! Once you have done this, save your game and use a file-editor to edit the file. NOTICE: When editing, be sure to have the Current sector and ending sector at the same location, and above all, backup your save game file! Change all the values to FF (e.g. FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF etc.).

The awesome thing about this hack is that you also get to research and build all the advanced buildings such as psionic lab and fusion ball defenses etc. early in the game! Also after changing all the weapon values, you only need to manufacture one of each item, and your inventory will indicate you have 255 or 226 of these items! Although some items may be in the research window. They might already be available i.e. Flying suits!). Best of all is you get lots of of elyrium!

One drawback is that the original author couldn't find the location for the UFO power source and UFO Navigation. Once you get these from a mission, he was not sure if these items will go to 256 (items) or you might have to re-edit the save game file to update/refresh your FF's.

One problem is the fact that your bases will have 255 scientists and 255 technicians (or whatever, can't remember their title). So you will not be able to purchase soldiers in bases 2 and 3 until you build enough living spaces for all the 255 scientists and other dudes and the soldiers themselves. You can try selling Scientists, etc. to make space.