Pause the game while playing as Crypto, then hold L and press X, Y, Left(2), Y, X. If you entered the code correctly, a message will appear.
Pause the game, then hold L and press Left, Y, White, Right, Black, X. If you entered the code correctly, a message will appear.
Pause the game, then hold L and press Black, White, Y, Right, White, Y. If you entered the code correctly, a message will appear. Your concentration meter must be above 0% or you will not be able to use any of your mental abilities.
Pause the game while on the Mothership, then hold L and press X, Y, Left(2), Y, X. If you entered the code correctly, a message will appear. All upgrades for the currently unlocked weapons will be available for purchase from Pox's lab.
At the Mothership's main menu, hold L and press Black(2), White(2), Left, Right, Left, Right, White, Black. If you entered the code correctly, a message will appear.
Pause the game, then hold L and press Right, X, White, Black, Right, White. If you entered the code correctly, a message will appear.
Pause the game, then hold L and press White, Right, White, Black, X, Right. If you entered the code correctly, a message will appear.
Pause the game, then hold L and press White, Black, Right, Left, X, Black, White. If you entered the code correctly, a message will appear.
Pause the game, then hold L and press Y, Black, Left(2), White. If you entered the code correctly, a message will appear.
Pause the game, then hold L and press Black, White, Black, X, Black, White(2). If you entered the code correctly, a message will appear.
Pause the game, then hold L and press White(2), Right, X, Y, Black, White, Black. If you entered the code correctly, a message will appear.
Pause the game, then hold L and press White, Right, Left, Black, Y, White, Black, X. If you entered the code correctly, a message will appear.
Collect all the probes in the indicated side mission to unlock the corresponding movie in the "Furonigami" option under the Archives menu:
- Art Of The Furon: Santa Modesta
- Blue Book: Saucer Blueprints: Rockwell
- Evolution Of An Alien: Turnipseed Farm
- Face of the Enemy: Area-42
- Pathetic Humans!: Union Town
- The Concept Barnyard: Capitol City
- Blue Book: Saucer Blueprints: Rockwell
Successfully complete the indicated level to unlock the corresponding movie under the "B-Movie Theater" option:
- Furon Down!: Furon Down!
- Outro Movie: Attack Of The 50 ft. President
- Plan 9 From Outer Space: Teenage Zombies from Outer Space
- Teenagers From Outer Space: Attack Of The 50 ft. President
- Outro Movie: Attack Of The 50 ft. President
Successfully complete the Attack Of The 50 ft. President level to unlock the following entries under the "Furon Propaganda" option: Crypto, Phone Home!, Developer Darwinism: Evolution Of The Game, E3 Booth Footage, and Goofy Screenshots And Voice-Overs.
Allow the game to idle for awhile; eventually the screen will turn black and white and elevator music will play in the background.
Allow the game to idle at the mission selection screen and Pox will make various remarks.
When you pick something up, you can control it with the Right Analog-stick.
Enable the "Bulletproof Crypto", "Ammo-A-Plenty", and "Deep Thinker" codes, then get all of Crypto's upgrades. After this you can turn into a human and walk around TK'ing everything.
Enable the "Bulletproof Crypto" and "Ammo-A-Plenty" codes while on your saucer. It will not get damaged or lose ammunition.
Instead of holding R to destroy buildings or large objects, tap R and the destruction will happen faster without waiting for the recharge.
While trying to hypnotize people, quickly tap X.
While extracting a person's brain stem (alive or dead), quickly tap B. You will get their DNA easier. This is useful against the M Agents and Psi G-Men.
While using the jetpack, quickly tap A to go farther distances.
Don't bother trying to run away from the authorities with short legs; use your jetpack liberally to fly away. Press Left Analog-stick Forward and hold A to boost away.
Enter a collect brain stem puzzle and find out how many brain stems you need. Then, stand around and extract the brains and leave them laying close by. When you have enough, go to the challenge and enter it; you can easily win by doing this.
After unlocking Area 42, you should see some bunkers that represent bomb shelters; they all have ammunition inside.
Probes are necessary to get upgrades quicker. In order to find them all, make sure to look high up on rocks or hard to reach places. Your jetpack is essential in getting to the high places. You may have to get up on the ledge or building, then use your jetpack to fly higher to get the probe. Also when you are in Capitol City, you can find about ten probes by the broken Pentagon.
If you need extra DNA, go to the Turnipseed Farm level and extract as many brains as desired. The Anal Probe Gun is a good weapon for this. It's much easier to use than rapidly pressing B to extract the brain stems of humans, as one charged shot from the Anal Probe will make their brains explode. You need three successful hits on Majestic Agents, two successful hits on the soldiers, and one hit for the policemen. Normally you can choose to extract your brain stem with the probe button (L) and tapping B rapidly to extract DNA faster. However this is not an effective tactic to use as Majestic Agents and soldiers take more concentration to extract their brain stems. Forget the concentration meter and use the Anal Probe Gun. To aim, use the Right Analog-stick and place it over a human. Then, hold R to charge up the Anal Probe Gun. Release R to fire at the selected target. One shot is all that is needed to take down some humans, but others may require more. However, you have infinite energy with the weapon.
Every chance you get, do not kill a human before you extract their brain stem. Extract their brain stem first as it will make the DNA worth more (25 instead of 10). The easiest humans to do this to are the scientists in the level with glowing cows. For some reason, if the person that is important to you dies (the person you need to abduct), extract their brain stem before you return to the Mothership -- the DNA is usually worth more. Additionally, it is rare to find humans with brain stems that are worth 50 or 100 DNA. Most humans have brain stems that are only worth 10 or 25 DNA. If you walk around Union Town, there will be humans with signs on them reading, "REPENT THE END IS NEAR". Those humans will have a brain stem worth 50 DNA. Also, Mystery Agents' brain stems are worth 25 DNA points most of the time, whether dead or not. The Psi G-Men are worth 150 DNA alive and 75 DNA dead.
After you complete the game all brain stems will be worth more when you use the anal probe:
- Citizen from 10 to 15
- Cops from 25 to 40
- Repent Men (Union City) 50 to 75
- Army from 25 to 40
- G-Men from 50 to 75
- Cops from 25 to 40
When Pox has you take out the President, just run up, extract his brain, and take it to get 200 DNA; this is the most you can get from a single human. To get more DNA from humans, first use Hypno on them. For example, using Hypno on a town crazy (the one with the sign) can result in 200 DNA. To probe a Majestic Agent, cycle to your anal probe and charge it. Then, shoot the agent. Do this three times and the agent's brain will come out; it is worth 75 DNA each time.
After getting out of your UFO, aim at a human and press B. When you have changed into the human, the bar on the top left corner of the screen will go down. When it is all gone, you will change back into an alien. If you want to remain human, turn into a human and while walking around, scan other humans or animals to make the bar on the top left corner stay up. Additionally, turn into a human then enable the "Ammo-A-Plenty" code. You will stay human forever. You do not have to scan thoughts to get out of the human body -- just press B.
Put your target (dot in the middle of the screen) on any human, and press B. In order to maintain your HoloBob, you must read the thoughts of the humans walking around. You can read the same person's thoughts repeatedly to keep your mental powers charged.
There are four basic icons for the awareness levels at the top of the screen. The first one indicates that civilians are aware of your presence and its color is purple. The second one indicates when the police are sent to investigate, and are on the scene with a yellow car symbol. The third one is a big orange star, which indicates that the military are involved. The fourth one is Majestic, a top secret government agency which has the power of seeing through your disguise and bringing you down with high tech weaponry. When you alerted to the police and the military (the orange star and the yellow police car) you can disguise yourself as a soldier for the military alert level or a policeman disguise for the police alert level. You can just use a normal civilian disguise for the first icon. You can also find hiding places or use your Jetpack to escape. For the Majestic alert, disguise yourself as one of them, but do not get too close or your disguise will deactivate, revealing your alien form. The Majestic symbol is a big red M. Keep moving when you fight them and look for out men in black with big green guns.
To get on top of the Santa Modesta's SMCBS TV station towers, first get on top of the station's roof. Then, jump onto the satellite dish and from there, to the slim post. Once on the post, jump and use the "Extra jetpack distance" trick to reach tower 2. From tower 2 you can also go to the other tower. From that altitude the police, army, and Majestic cannot see you. Use the Ion Detonator to blow them up. This is best done when aiming down before jumping; you can then see where you are landing.
Find the monument, then throw cars at it until it breaks into two pieces. Get on the long pointy piece, PK the middle, and try to stay on.
When you are in the form of another person, to make you brain juice meter go down, read other people's thoughts.
Enable the "Bulletproof Crypto" code, then get on top of a car (military trucks and tanks work best). Aim your Ion Detonator at the vehicle. Detonate it and you will be shot into the air. You can use your jetpack to fly away.
When you have to defend the radio towers, you will get to use the atomic blast in your space ship. However, be very careful, because if you shoot too close to the towers it will bring down their health even more.
Use your PK ability on a Majestic limo; hold L the whole time. Get a wall between you and the car, then start running away from the wall until the car smashes into it. Keep running backwards and the car will eventually explode. This trick can also be used to take out normal cars and people.
It you levitate a person for a long time, they will die.
Stand in an open area on any level and walk forward. Keep decreasing your speed until you eventually begin walking in place.
When done with a mission at Capital City, enable the "Deep Thinker" and "Bulletproof Crypto" codes. Then, go to the bridge that goes to the octagon. Attack the people to get the robots to attack you. Use the mind control on the robots and lay them about over the edge. You can see a robot arm pulling the robot into the water.
If you scan a Psi-Mutant a few times, he will say "Algernon... Good mouse... Smarter... than... Charley". The Psi-Mutant is thinking about the book, "Flowers For Algernon".
In the final mission, scan Silhouette's mind. Eventually she will think "What was I doing? Oh yeah. The same thing I do every night. Try to take over the world!".
Halfway through the game you will experience a level where you go to the drive-in to switch films with the one that is showing. Watch what is showing before you switch films to see that the film is Edward D. Wood, Jr.'s Plan 9 From Outer Space.
Scan a cop in the Santa Modesta area and you will eventually hear, "If only I had a cowboy, an Indian, and a construction worker."