Metal Gear Solid 2 Extras
Warning: This section may contain spoilers.
Unlockable:
Stealth:
Tanker: Collect 60 dogtags
Plant: Collect 120 dogtags
Infinite Ammo/Other:
Bandana (Tanker): Collect 30 dogtags
Brown Wig - Infinite Ammo (plant): Collect 100 dogtags
Blue Wig - Infinite O2 (plant): Collect all dogtags
Orange Wig - Infinite Grip (plant): Collect 150 dogtags
Unlock Extreme Mode:
Beat the game once on any difficulty.
Increase Grip Levels
You can increase the amount of time you are allowed to hang from railings. This is done by doing "pull-ups" which is just hanging over the edge and then holding R2 and L2 to do a pull-up.
Grip Gauge Level 2 - Do 100 Pull-ups
Grip Gauge Level 3 - Do another 100 pull-ups after unlocking the Gauge 2.
*As an alternative, dropping down railings (done by already hanging, then pressing X to fall and immediately pressing Triangle to catch another raililng), is equivilant to 10 pull-ups.
Unlock Digital Camera:
Beat the game once.
Easter Eggs:
Hilarious Otacon Conversations:
If you use the standard camera that came with the mission, you can have fun by taking pictures of posters plastered around the tanker, or simply random stuff throughout this mission. Once you upload them to Otacon, he will have a message depending on which picture is displayed. Some pictures that are displayed multiple times, Otacon will get really fed up (Hint: be sure to take several pictures of someone talking, or the girl posters).
Mind Reader:
In any codec conversation, tap R2 or L2 to hear what your characer is thinking during the conversation.
Pliskin Caught in a Box:
In the plant chapter, after the talking to Peter Stillman with Pliskin, immediately go outside the nearest door and look in first person view. You will see a guard laying unconscious, and Pliskin running around in a box. If you call Pliskin, he will appear suspicious. Also, you don't need to have experienced this Easter Egg to see this, but when you watch a cutscene later that shows Olga talking on the radio, she will say something about a man running around in a cardboard box.
Bathroom Issues:
After finding Ames, you will eventually find yourself holding the Microphone. Turn it left easily away from the conversation that you are supposed to be listening to. You will hear someone having Diarreah issues in the bathroom. It is rumored to be the same soldier from Metal Gear Solid 1 that also had bathroom problems.
Disoriented Guards:
If you get caught by a guard and are lucky enough to be aiming in first person view, you will see an exclamation appear over the guards head. If you shoot it, the guard will become dazed.
Make Rosemary Mad:
There are a couple of ways to make Rosemary mad, while the Colonel encourages her anger towards you.
When you are outside, shoot any birds you see. If you kill enough, you will get a call.
When you are in room looking for Ames, do a kick/punch combo on one of the hostages and you will get a call.
Inflict Lag:
This is not so much an Easter Egg, but it can be humorous. Plant a bunch of claymore mines on top of each other and wait for a guard to walk over them. You may get an alert, and smoke all over your screen but it will take a few seconds for the game to catch up. This may temporarily cause you to move slowly, while watching the Alert bar fill at about 1/4 of the speed. This all depends on how many mines you use. If you walk over it yourself, you will automatically die, and the Game Over screen will take longer than usual to appear.
Snake is Feeling Lonely:
In the tanker mission, go inside one of the lockers with one of the girl posters. Look at their face in 1st person view. If you done this right and call Otacon, he will be annoyed with Snake for... nevermind...
Misc.
"Freeze!" (Collecting dogtags):
Getting dogtags is a pretty simple task if you know how to do it. Just make sure a handgun is equipped, then sneak up behind a guard and hold Square to aim. You'll know you did it right when you hear "freeze" from the character you're playing, and then the guard holds his hands up. Then go around and in front of the guard (do NOT unequipped your gun). Then aim your gun at their head or their "sensitive" area and most of the time, the guard will forfeit a dogtag. If you already collected a dogtag from that guard on that difficulty, you will get an item instead. In some cases, the guard will be stubborn and ask if you will really shoot them. If you have a lethal (non-tranquilizer) gun, you can shoot their arm or leg to prove that you are willing to inflict harm.
Preventing/delaying alert mode:
There are a couple of things you can do to delay an alert phase if you've been spotted.
One way is to shoot the guards radio from behind. If you land a direct shot, you will see the radio sparking. If you are then caught by the guard, he will go for his radio and attempt to use it but realize it's broken. When they realize it's damaged, they will run out of the area to get a new radio, which gives you a chance to get out as well before the guard comes back with a new radio to put you under alert.
Another way is if you get caught by the guard and are quick enough, you can do a punch/kick combo to stop them from getting to their radio. If you are too close, the guard will kick you to the ground which will make this harder. If you do manage to knock the guard down, either get out of there, or continue to beat him until he's out. If he was in the middle of calling his friends, you can still take him out, but the commander will have troops sent in to investigate. If you knocked him out, you should atleast use your tranquilizer to put him to sleep. Once the guards come around, they will wake him up and the guard will just be confused and go back to his routine, but if you only knocked him out then he will initiate a Caution. You can also hide the enemies body in a locker if you accidently killed him.
Waking up soldiers:
This is common if you are collecting dogtags and you shoot the guards with your M9. Use your coolant spray or drag their bodies to wake them up faster. If you have the coolant, it will be much faster.
Run while Aiming:
A neat feature is being able to run around while aiming your gun. While holding down Square, you also need to hold down the L1 button which will enable you to move around. This is a good method to use if you are collecting dogtags.
Climing on Stuff:
Walk up to a box about waist high and press the action button (that would be O on the Playstation).