We've Got Hostiles: Easy completion
When starting the"We've Got Hostiles" level, turn to your right and use the /noclip code to float through the glass window with the security guard being eaten by the zombie. When you are in there, press the switch that opens the Silo and the Silo door will open. Float back out of the room, disable the noclip code, then go through the Silo door to start the next level.
Zoom on every weapon
Get the Crossbow in single player mode and do a quick save with the weapon that you want to zoom in with. After that, change to the Crossbow and zoom in, then quick load and your other weapon will be zoomed in. You can now change weapons and they will all be zoomed in. To come out of zoom, change back to the Crossbow and press the second fire button until it zooms out again.
Advance to final Boss
Activate the console window and go to the Hazard course. When you reach the bridge to get the hazard suit, jump of it into the sludge. You should be teleported to Nihilanth automatically.
When starting a game and you get your suit, look at the lockers. One will be marked "Freeman" (your character's last name). Walk straight to it and you will see a photo of his little boy or girl.
Cheat Codes (alternate)
Start the game with one of the following command line parameters to activate the corresponding cheat:
When first starting the game, enable the /noclip code to jump out of the tram. Then, walk to the end of the pathway and jump down to the helicopter. Speak to the men in the cave to hear dialogue that should be from after the "accident" but are not.
In Single Player mode, after shootingthe missile enable the /noclip code and chase it. Let it go completely out first, then leave. As soon as you leave the area, disable the /noclip code and turn on your flash light. You are now in a hidden room.
Dislocated body parts
After the disaster, in anti-gore mode, select any level and shoot down one of the men. He may not disappear. If he does not, keep hitting his bag with a crowbar (if visible). He should appear have all his body parts dislocated. Note: This occasionally works better if you creep up behind him with a crowbar or enable the /notarget code. To get in anti gore-mode, go to the options menu and use the password protected area on the visuals.
Game Of The Year Edition
On the level where you must pick up your HEV suit before the accident, enable the /impulse 101 code and select the crowbar. Walk up to a scientist and wait for him to do a scripted event such as scratching his chin while looking at computer readings. Keep hitting him with the crowbar. When the scripted event ends, depending on how many times you have hit him, there will be an explosion of meaty chunks.
Play the On A Rail level. In the dark place were you crawl through, look on the wall to see the word "Riller". Dave Riller is the name of someone in the starting credits.
Activate cheat mode, then use the /impulse 76 code to activate the Grunt-O-Matic. A message to start a new game in order for it to work will appear. If you want to continue where you currently are, just quicksave, then quickload the game. Once you have quickloaded, type in the code again to spawn a Grunt. Note: You must have the /nocliping code on before you spawn the grunt because he will be spawned close to you. If this is not done, a message stating that the monster spawned is stuck in a wall might appear and the game will end. Don't spawn the Grunt in a closed position or the same message will appear. The Grunt you spawn will see you as a hostile. To have more fun, use the /notarget code and spawn a number of grunts to do your alien hunting.
There is a deep voiced scientist on level 1, in the room before the test chamber. When you ask him to go with you he will have a high pitched voice.
Look inside G-Man's briefcase
To look inside G-Man's briefcase, first enable the noclip code. There are two ways to do this trick: the first is to begin from the start and ride the train until you see the G Man for the first time. He should be in a train next to the one you are in towards the end of the ride, by the radioactive water. The other way is to go through the train ride, then walk around the halls of the laboratory to find him talking to a scientist. When you do this, go towards the G-Man. Get as close as possible to his briefcase without going through it (this make require several attempts). In one side, there is paper, three pencils and a pistol. On the other side is a computer with a message and a picture of the G-Man. Note: When doing this where the G-Man is talking to the scientist, you will not be able to understand what the two are saying.
Avoid wasting precious pistol ammo on headcrabs. Use your crowbar, as it is more useful.
To activate codes easily, bind them to keys. For example, type /bind v "impulse 101" at the console window to bind the "HEV suit, weapons, and ammo " code to the "V" key.
Gene Worm strategy
When you reach the "World's Collide" level you will be close to the head Boss, a Gene Worm. To kill him you must shoot his eyes out with the two mounted laser guns. When both eyes are shot out. his stomach will open up and a large pink orb will appear. Keep shooting the orb until his eyes come back. Then, repeat the steps of shooting his eyes and the orb until he dies.
Using the pistol
Use the following list to save ammo for all guns other than pistol. The following creatures can be defeating by the following number of pistol shots:
More powerful shotgun
While using the shotgun, right click to shoot two shots at once. This kills everything twice as fast.
Barney gets cut in half
When you enter the room where the lasers are shooting out the walls, run through. There should be a Barney (security officer) on the floor. Watch carefully and you can see the laser go across and literally cut him in half.
Find a headcrab, then jump on top of it and look down. You should see that it first jumps, then it starts to dance. Kill the headcrab when you want to exit.
When you have a guard, get him close enough and he will take care of almost anything for you. The only time you ever need to fire is if the creature is close to the guard.
If you jump or fall from a high location, use the Tau Cannon Gun (gun hat fires orange bolts). When you fall, use secondary fire to hold it and release it immediately before you hit the ground. You will land without losing health. You can use this technique to get to high places by doing this from the ground.
Grunt smell comment
During the first level, enable the /impulse 101 code and go to either one of the two security officers (Barneys) guarding an area. Use the /impulse 76 code to spawn a Grunt near them. Do not spawn the Grunt in a wall or Barney or the game will end with an error message. Kill the Grunt quickly and leave it on the floor for a couple seconds. Barney should say "Ew, what's that stench?" or something similar.
HEV suit falls out
Activate the /impulse 101 code while in mid-air and an error saying the hev suit has fallen out will appear.
Cheats on first level
If the all weapons and ammo cheat code are enabled during the first level of the game, on the train, an error message stating that the hev suit fell out of level will appear. The game will automatically quit.
Spawn Barney in War with Nihilanth
Usuallywhen you want to spawn Barney at the Nihilanth episode, you will get an error message. To solve this problem, go to Lamba Core teleport to Xen. Enable the /noclip code. After the scientist finishes his teleport to Xen, go through and dark. After that, type give monster_barney repeatedly until you arrive. You will go to a strange island and not have a Barney, but you must type it. After that, you can play and fight with Barney at the alien world. You also can do this at Nihilanth teleports. The v18.104.22.168 patch no longer allows this to happen.
Chat key bindings
You can enter bind "p" "say Hello" or bind "p" "teamsay i need backup" and press ENTER at the console window to bind those and other chat commands.
In multi-player on LAN games, create a game and select a level with the Zapper in it. This is the gun that you hold the RIGHT MOUSE BUTTON to charge and shoot. Aim it at the ground and you will jump high. Note: Be careful where you aim when you fall because you will lose health. This does not work in Story mode.
You must be within the loading area of the desired monster for this cheat to work. For example, you cannot load up Barney while fighting the Nihilanth. Enter give and the corresponding monster will appear. Note: Activate the /noclip first, or you will be stuck inside the monster.
Item name list
Fun with spawning
Activate cheat mode, then use the entities code to get a list of the creatures in the location you are currently in. Usually, when you try to spawn a creature, you have to use the noclip code to levitate in the air and spawn the creature nowhere near any objects. If a part of a spawned creature is spawned within a wall, ceiling, or another creature, the game crashes. However, if you enable the developer 0 code, the game keeps going even if a spawned creature is stuck, but the creature has yellow dots around it. Also, bind the spawn commands to unused keyboard keys; for example bind X "impulse 76" or bind y "give monster_scientist". The impluse 76 code works everywhere, and the hostile grunts created with it are easy to place where you want them; as they appear in front of you, rather than above. Now, enable the noclip code and fly around pressing the bound keys. Watch as Barney's Aliens and Grunts battle it out while Scientists run around being slaughtered.
Load game with the command line: hl.exe -dev -toconsole. Then, press ~ if the orange text on the screen does not disappear. During gameplay, press ~ to display the text prompt and type in sv_cheats 1. Press ~ and activate the following cheats by entering the corresponding codes:
You can kill Gargantua when you meet him again in the parking lot. Immediately as you walk into the parking lot in the Incoming section of the game unload all your missile launcher ammo, at least six grenades, and four Tau Cannon charged shots, and how clip from a combat rifle to kill him.
Items from the console
Go to the start menu, all programs, accessesories, and then click on command prompt. Select you Half-Life directory and type hl.exe -console then Half-Life should open. Start a new game then press the ` (tilde) key, then activate the following cheats by entering the corresponding codes:
During the "Apprehension" level, you will come across a part where you go through two red doors reading "CAUTION" that lead into an area with a large sunken in area, two military officers, and a turret gun. Kill the two officers (you can use the turret gun if desired), then turn and face the direction opposite the wall with the door and the large window. Enable the "No Clipping" code and walk forward through the natural wall. You will see a large yellow shaft. When you get closer, you will see a huge rocket inside.
Right before the accident you will enter a room with two scientists. They will talk to each other. After they are done and have opened the door, make one of the scientists stand on where the door should be. Once you go into the room, the door should shut behind you, with the scientist trapped in between it. Once you have put the rock into the laser, run into the room with the two scientists and hide out of sight from the laser. This should make the sequence to Zen not happen. When the next chapter begins, the scientist you trapped in the door should still be there.
During the third part of the "Interlooper" level, get to where you see a Garg (a huge monster who can burn you) crushing rocks and stones. To be able to pass through, there will be a small hole behind. When you enter it, you will find a little waterfall and plenty of water on the floor. When you step into it, your health will gradually recover. Before entering the hole, look in the direction where the Garg crushes the huge rocks. You should be able to see a sort of smooth staircase-like slope. It will be on the left, stuck to the wall. Climb on it. When on top, look to the right to see a tiny lighted room with med-kits and ammunition packs. Duck, and crawl into it.
See G-man and Gordon
At the end of the game, after G-man asks you to select between his employment or death, walk into the portal. As the credits start, enable the brightness 9999999999999 code. You will see G-man and Gordon standing next to each other. You can also enable the chase_active 1 code to get a better view. Note: This will also happen if you decline his offer.
Hidden scientist message
Start the game with the -console -toconsole -dev command line parameters. You will see a constant flow of text after doing anything. Use a low damage weapon on a scientist, then run after him. Once he is trapped somewhere press USE on him. The text should say similar to "I won't follow you, you evil man".
Map name list
Talk to dead man