StarCraft 2: Wings of Liberty
Activate the game console by pressing [Enter] while playing. After that, just type in the cheat below to activate the corresponding effect.
Lost Viking Cheats
Enter these codes in the chat box while in the Lost Viking mini-game. The Lost Viking mini-game can be accessed by left-clicking the arcade cabinet in the Cantina, and the chat box can be opened by pressing ENTER. Note: The dashes that precede most of the codes must be entered as well.
NOTE: As long as any cheat in StarCraft 2 is active you won't be able to earn any achievements.
Left click any creature several times to make it explode.
Units hidden dialogue
Keep left clicking units to hear secret dialogues.
Secret Mission: Piercing the Shroud
To unlock the secret mission, on the "Media Blitz" mission, where you get to control the Odin in the city, head down to the far bottom right corner of the map. There's a civilian building on a little floating platform. Destroy it, and "secret documents" will be revealed. Pick these up with any ground unit, and then complete the mission as normal. After, you will now have the secret mission available for selection from the Star Map.
Alternating Background Screens.
Complete the Campaign.
Unlockable Songs for the Juke Box
Cow Chat Channel
When in the Starcraft 2 menus press the blue symbol under the title. This will place you in a public chat channel called cow. Every time you speak your message will be followed by ...moo!