To begin cheating open [Half-Life 2] In Steam then when the game is done loading and your at the menu go to [Options] then to [Keyboard] at the bottom you should see something that says [Advanced] click on it and Check the box that says "Enable Developers Console" then exit out of [Options] and press "~" key and wallah! you have a console! Now go start a level it doesn't matter which one they all work with the console. Once your game has loaded hit the "~" key and you can start Cheating here are some of my favorite ones. Note: enter these cheats in the console!
TO ENABLE THESE CHEATS FIRST TYPE "sv_cheats 1" in the console w/o parenthesis.
Cheat name: Cheat Effect on Game
impulse 101 Gives the player all weapons
impulse 82 Spawns a Jeep a.k.a. (scout car)
impulse 83 Spawns an Air boat
God Gives player infinite health
Buddha Health never goes below 1
sk_max_357 999 Gives the revolver 999 bullets
sk_max_ar2 999 Gives the Pulse rifle 999 bullets
sk_max_ar2_altfire 999 Gives the Pulse rifle 999 Energy Orbs
sk_max_buckshot 999 Gives the shotgun 999 bullets
sk_max_crossbow 999 Gives the crossbow 999 arrows
sk_max_grenade 999 Gives the player 999 grenades
sk_max_pistol 999 Gives the pistol 999 bullets
sk_max_rpg_round 999 Gives the RPG 999 bullets
sk_max_smg1 999 Gives the SMG 999 bullets
sk_max_smg1_grenade 999 Gives the SMG 999 RPG's
If you want to give yourself weapon by weapon instead of typing impulse 101 in console here is the guide.
To give yourself a weapon type give weapon_
Below are the weapon names you put in place of
357
ar2
bugbait
crossbow
crowbar
frag
physcannon
pistol
rpg
shotgun
smg1
Now for the NPC's guide
First to create an NPC type "npc_create npc_
cscanner
rollermine
poisonzombie
mossman
monk
metropolice
manhack
launcher
kleiner
ichthyosaur
headcrab_poison
headcrab_black
headcrab_fast
headcrab
helicopter
gman
fastzombie
eli
dog
pigeon
seagull
crow
combine_s
combinegunship
combinedropship
citizen
breen
barney
barnacle
antlion
alyx
antlionguard
stalker
strider
vortigaunt
zombie
zombie_torso
turret_ceiling
turret_floor
combine_p
To create an NPC with a weapon type npc_create_equipment weapon_
note: not all weapons work with NPC's
The last thing to go over is "Binding". Binding is when you assign a key to a cheat command for example bind x "impulse 101" now every time you press the "x" key in-game you have all the weapons in the game.
You can also assign NPC's to a bind key for example bind x npc_create "npc_zombie"
now every time you press the "x" you have a zombie note: you must be looking at a surface for example look at the ground when you press the "x" key dont press x while looking in the sky or nothing will happen.