Type :debug and press ENTER during single player game play. Then, activate the following cheats by entering the corresponding codes and pressing ENTER.

Effect	Code
Get gold	:gold [0-999999]
Set experience for highlighted unit	:unit experience=
Set health for highlighted unit	:unit hitpoints=
Set movement for highlighted unit	:unit moves=[1-99]
Set unit level	:unit level=
Spawn unit	:create []