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You can only enter cheats during gameplay. To enter a cheat: first press Enter, then type the cheat phrase (case sensitive?), and then press Enter again. For all cheats you must enter Corwin of Amber first.

Note that you can enter cheats in head to head matches (multiplayer), but that both players will gain the effects of the cheat.

Cheat Phrase	Effect
Corwin of Amber	Cheat codes enabled.
Orc #/Human #	Changes the current map to the desired campaign level #.
Ides of March	View the campaign victory video.
Yours Truly	Instantly win.
Pot of Gold	Instantly receive 10,000 gold and 5,000 lumber.
Eye of Newt	All spells researched.
Iron Forge	All armor and weapon upgrades researched.
Sally Shears	View the whole map.
Hurry Up Guys	Increases the rate of research and the movement and attack speed of any newly recruited units and constructed buildings.
There can be only one	All of your units and buildings become extremely durable.