Here are some XCOM: Enemy Unknown and Enemy Within hints, tips and tricks submitted by rusted and updated by Geo. (Updated 1/29/01)

1) Live Aliens are your friend. They can snowball EVERYTHING else in the game (See money spoiler). They give you weapons intact, they give you research bonuses, intact weapons and easier research let you focus on:

2) Engineers beat Scientists in this game. Engineers run your satellites and make them cheaper, Satellites win you the game. Those country bonuses you think about when selecting your base?

They don't really matter. If you cover the countries in the continent with Satellites, you get the bonus as if you had a base there. North America and Africa are synergizing the best in my current game.

However in every... freaking.. game... every...one... Egypt is incredibly difficult!

3) Money Cuts the Rope. There isn't a Laser Cannon racket you can run here. You will be pressed for money at least till mid game. At that point, if you remember rule number 1&2 ;You will get delivery pop-ups for X number of Y weapons, it seems that after mutons these are Plasma and Laser weapons.

These requests are always a huge profit.

Much more so if you've been been getting these items off the aliens as opposed to manufacturing them. I've had a few Plasma rifles or Plasma pistol offers at about 3k. This influx is huge and lets you snowball.[1]

4)The game will tell you what sell on the grey market. The game will clearly state what is harmless to sell. That said Don't sell Alloys, you'll need them. Weapon fragments are somewhat safe mid/late game and if you budget Elerium sales can get you out of a bind.

5) When selecting missions: 5th Red Bar > Engineers > Scientists > Recruit (Capt. or Higher imo) > Money > Recruit

6) I'm actually not using a foundry this game. The refunding and Shiv's are nice, but I don't like how they don't advance as well, and they're pricey when I could be buying Sats. No trolling, but I see some serious potential with the pistol line of research though.

7) As far as tactics, I think this will actually be the easiest part of most people. For me: 2 Assaults every mission, they're supposed to fall off, but I haven't seen it.

At higher levels supports are also a force. I really don't find my heavies doing that much, and my sniper is mostly just overwatch. I tend to recruit Zerg the UFO and Terror Missions.

Abuduction missions I use to level up my better troops as they're fairly linear. Any escort or VIP mission will be a gear check. Seriously they are beast. The easiest might be the bomb ones and that's only because you eventually hard counter poison.

8) Just to note, in the left hand corner by your troops name, that Star... that's your Squad leader don't let him die changes per mission, usually your highest ranking or most mission dude.

9) F1 while your soldier is selected will tell you your current bonuses or penalties in combat. You can quick view this with a small ^ next to your soldier on screen. Green=Good, Red=Bad.

10) Last, do not disassemble your Officer Training once the research is completed. Seriously this was huge and at a truly dangerous time, totally caused my previous attempt to wipe.. If you destroy it you will lose all the abilities it provides, you don't lose the research if you rebuild it, but if it's gone you're back to squad size 4 and other problems.

Some more random tips and tricks:

• When you encounter an enemy, if you have a heavy with supressive fire, save using them until you fire with all of your other units. That way, if somehow all of your other guys miss, your heavy can suppress the enemy until the next turn when you get another chance.
• When moving your troops, always move within the blue area first. (Don't dash) That way if you encounter an enemy, you can fall back / regroup and not be caught off guard.

  Also once you discover an enemy, make sure not to move any unts past the place where you discovered the enemies so that you don't trigger even more enemies further in the map.

  The only time dashing is good is at the very start of the level, on turn 1. This is because enemies are further into the map, and one turn of dashing won't trigger them most of them time. Still it's best to be careful, and not rush things.

• Many times when encountering enemies, it's better not to rush in and attack with a unit. Instead fortify, get in position, and stay hidden, until of your units are in position to attack together.

  Once they are all ready, then attack at the same time. This way you can put a unit on overwatch, and have it cover all of your other units that are advancing on the enemy.

• Try to keep your medic away from the front lines. In case one of your units gets damaged, you want to have your medic to heal them!
• When preparing for an attack, first get in position and keep your units hidden until they are all ready to attack together.
• Deploying satellites increases your monthly funding, so try to get them going early on.

  You also want to have satellites on every contintent to get all the bonuses possible.

• The Arc Thrower is a very powerful tool. Not only can it stun and capture aliens for research, it can also dispatch powerful enemies in one shot!
• Keep in mind sometimes it is more beneficial to switch to a pistol to attack an enemy instead of going for a low chance shot (like with a target that is too far away from you with a shotgun).
• With Enemy Within, we have a new resource called MELD. While MELD is very useful for having your own Mec units, it is not mandatory.

  It may seem like getting MELD is a must on every level, but don't stress it too much. As long as you can grab a little Meld every few levels, you will have enough to build enough Mec units.

• Speaking of Mec units, they are incredibly powerful. Having 2 or 3 on your team can really help in difficult missions. Though you probably still want to have a few regular soliders because of the flexiblity of items they can use.

  Mec units are also immune to aliens that one shot your regular units, and turn them into zombies. Mec units can't take cover, but have a lot of HP and can take more hits than regular units.

  Mecs can also use the Flamethrower which can make enemies panic on top of taking 6 damage.

• Alien Base Preperation - When you get an event to assault the alien base, I would advise against taking it until you are ready.

  While alien base assault missions aren't too difficult on their own, the counter-assault from the aliens can be a run ending moment if you are not ready.

  If you do decide to take out the alien base, make sure you have at least 8 strong, well equipped soldiers (laser rifles recommended) ready to defend your base for an attack within one month of your assault. Rookies just won't do.

  The best advice I can give you for when the alien counter-attack begins is stay in cover and move slow. The aliens will first attack from one side, and then they will try to flank you.

  Another good tip for defending against the alien attack is to get some of your units to high ground (upstairs). Having a few snipers and other powerful units at the top will both protect you from attacks, and give you a better vantage point.

Have any other XCom Enemy Unknown hints, tips or tricks? Post them in the comments below. Thanks for visiting.