Quake II

You need to type these cheats in the console. Activate the console by pressing the tilde ~ key.
 

Code Description
give all Get all items
give health Increases your health points by 100
give weapons Get all weapons
give ammo Get 100 shells, 200 bullets, 200 cells, 50 grenades, 50 rockets, and 50 slugs.
give armor Get body armor
give body armor Increase body armor by 1 point
god God mode
notarget Enemies won't attack you until you shoot them
noclip Walk through walls
give jacket armor Get jacket armor
give blaster Get blaster
give shotgun Get shotgun
give super shotgun Get super shotgun
give machinegun Get machinegun
give chaingun Get chaingun
give grenade launcher Get grenade launcher
give rocket launcher Get rocket launcher
give railgun Get railgun
give bfg10k Get BFG 10000
give shells Get 10 shells
give bullets Get 50 bullets
give cells Get 50 cells
give grenades Get 5 grenades
give rockets Get 5 rockets
give slugs Get 10 slugs
give quad damage Get quad damage
give invulnerability Get invulnerability
give silencer Get silencer
give rebreather Get rebreather
give environment suit Get environment suit
give ancient head Get ancient head
give adrenaline Get adrenaline
give bandolier Get bandolier
give ammo pack Get ammo pack
give data cd Get data CD
give power cube Get power cube
give pyramid key Get pyramid key
give data spinner Get data spinner
give airstrike marker Get airstrike marker (not included in "give all")
give blue key Get blue key (not included in "give all")
give red key Get red key (not included in "give all")
give security pass Get security pass (not included in "give all")
give commander's head Get commander's head (not included in "give all")
give power shield Get power shield (not included in "give all")
give armor shard Get armor shard (not included in "give all")
give combat armor Get combat armor (not included in "give all")