Change Attitude:

To alter your council's attitude and time period, enable Cheat Mode, then press Ctrl-Shift-T.

Edit Unit:

Hold Ctrl + Shift + U. You can now change all atributes except type of unit.

Edit the Throne Room:

To change your throne room, turn Cheat Mode on then press "Q" and click on the spot you wish to change.

Invincibility:

Type "god" during gameplay to become invincible
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Use Enemy City:

Infiltrate your enemy's cities. Press "V" and move diagonally into an enemy city and press ENTER. You can now change the city's productivity and disband unit