Adrenaline shots can be found on any level. Use an adrenaline shot then quickly revive a teammate 10 times for this Achievement. You can do this in certain safehouses in single player. Find a safehouse, like the first one in the Parish at the end of Act 1, and shoot your teammates until they are incapacitated. Use a shot, then quickly revive all three of them. Grab another shot and repeat this process a few times to get the Achievement.
Cheat: Cheat List
At the main menu, go to Options and toggle the developer console on. Now you'll be able to open your the console by pressing ~ (or the key above Tab).
Type sv_cheats 1 in the console. This will enable the cheats. When you get the message "sv_cvar_cheats_changed_to 1," type in the following codes for the desired effect. Note: these cheats are mainly from Left for Dead, and may not work in the sequel.
tongue_range X - (Default 750) Sets the maximum range of the smoker's tongue attack
z_pounce_damage X - X is amount of damage you want to do to survivors
z_witch_burn_time - X is amount of time before a burning Witch dies from fire (does not affect damage caused by fire)
z_health - Change Zombie Health
z_speed - Change Zombie Speed
director_no_human_zombies 0/1 - Toggles controllable Boss Infected on any map
director_panic_forever 0/1 - Toggles never ending panics
director_force_panic - Forces a panic event
give ammo - Full Ammunition
give pistol - Get Pistol
impulse 101 - Spawn Ammo To Your Primary Weapon
give autoshotgun - Spawn auto shotgun
give health - Spawn full health
give gascan - Spawn gascan
give hunting_rifle - Spawn hunting rifle
give molotov - Spawn molotov
give oxygentank - Spawn oxygen tank
give pain_pills - Spawn pain pills
give pipe_bomb - Spawn pipebomb
give propanetank - Spawn propanetank
give rifle - Spawn an Mk 47 (machine gun)
give first_aid_kit - Spawn first aid kit
z_spawn weapon_SMG - Spawn the SMG
god - Invincibility
buddha 1 - just like god but you receive damage(sometimes if you are the only survivor left you can't receive damage from infected)
sb_openfire or open_fire (console will tell) - makes your bot teammates shoot nonstop
director_no_mobs <1/0> - No mob rushes
firstperson - Play in first person (default); this cheat is only necessary if thirdperson mode is enabled
Ent_Remove - Removes All Bots
z_witch_damage X - Sets the amount of damage a Witch's attack does
thirdperson_mayamode - Sets the camera to be fixed in place while in either third person or third person shoulder mode Enter once to turn on and enter again to turn off
thirdperson - Sets the camera to be in third person mode
thirdpersonshoulder - Sets the camera to over-the-shoulder third person mode
z_common_limit - Sets the maximum amount of regular zombies
z_tank_health X - Sets the maximum health of the Tank
z_frustration_lifetime X - Sets the number of seconds until the player loses control of the Tank from not attacking survivors
sb_friendlyfire <1/0> - Toggles bot friendly fire damage
director_stop - Shuts off all wanderers, mobs, specials, and bosses
z_spawn zombie - Spawns 1 Zombie
boom - Spawns a active pipebomb under you
fire - Spawns a lighted molotov right on the floor under you
z_spawn - spawns a special infected (infected names: hunter, boomer, smoker, witch,tank, spitter, charger, jockey)
z_spawn mob - spawns a zombie horde
z_spawn boomer - Spawns boomer at location of crosshair
z_spawn hunter - Spawns hunter at location of crosshair
z_spawn smoker - Spawns smoker at location of crosshair
z_spawn tank - Spawns tank at location of crosshair
noclip - Toggles No Clipping Mode
z_witch_allow_change_victim <1/0> - True/False setting that allows the witch to change targets instead or focus on the one survivor that alerted her first
sv_infinite_ammo 1 - Unlimited Ammunition
Vocalize - Vocalizes/makes the player say anything like vocalize playereatpills
tongue_fly_speed X - x= amount of speed that you want for the smoker's tongue
z_pounce_door_damage X - x= desired amount of damage to pounce through doors
sb_give XXXX - x= desired entity to give to your bot teammates (the console should give you a list)
retry - You can unlock achievements while using cheats (after entering sv_cheats 1, enter retry)
Hint: Weapon Descriptions
Check the gunshop in Dead Center (first episode, second map) for an accurate description of every firearm in the game (except the grenade launcher).
Hint: Gong Show Achievement
In part 4 of Dark Carnival, look for a strength-testing game in the first area after exiting the safe room. Inject some adrenaline and nail the red button with a melee weapon to get the Gong Show Achievement (be "stronger than Moustachio"). Note: Will summon infected!
Hint: Stache Whacker Achievement
In part 4 of Dark Carnival, look for well-lit Whac-A-Mole-like arcade game near the start. Activate the button on the front of it and attack the Moustachios that pop up with a melee weapon. At a score of 46, the game will break -- you may need to continue a few times. When it breaks, you'll get the Stache Wacker Achievement (be "faster than Moustachio"). Also, the game will attract zombies.
Hint: Guardin' Gnome Achievement
In part 2 of Dark Carnival you'll come across a well-lit shooting range with carnival mascot Moustachio emblazoned on it. Also note the yard gnome in the box -- your prize for getting 750 points. Get this high score by activating the game (via the red button) and shooting everyone but the blue peanut (you'll lose points if you hit this target!). Hit the yellow and green Moustachio target for extra points. The gnome (which you may recognize from Half-Life 2 Episode 2) will be released if you get a high score and so will scores of infected, so beware!.
Carry the gnome all the way to the end of the scenario (board the chopper) to unlock the Guardin' Gnome Achievement. You can drop Gnome Chompsky and pick it back up. You can also drop it in a safe room and it will be there after the break. Finally, you can use the gnome to repel zombies as you would with a weapon.