Below I have compiled all of the Zeus, Master of Olympus cheat codes that I know to be working. These cheats range from silly to useful so even if you're a non-cheater, there's nothing wrong with some cheese costumes or cow missiles. There are some cheats out there on other websites which are wrong so I've only put here the ones I tested in-game though, for some reason, one cheat appears to have a mind of its own and only works for particular people.
Cheat codes:
Bring up the cheat box by typing CTRL + ALT + C and type in the following codes, case sensitive, to get the applicable effect:Delian Treasury: Add 1000 Drachmae (only if money is below 15,000)
Ambrosia: Win the scenario soon after entering code.
Lots of Fishy: Unlimited food (doesn't work for some, for some unknown reason)
SoundFrags: Animals make strange noises when they die.
Fireballs from Heaven: Strike a particular piece of ground with a fireball
Bowvine and Arrows: Towers will shoot cows instead of arrows.
Cheese Puff: Dairy workers will wear cheese suits.
Mammaldrome: Granaries are filled every three months.
Atlasthegreat: Atlas will build your project in ¼ of the time.
Seasick: Poseidon will grant you 10x the fish currently in your granaries.
Hotlava: Strikes the ground with a fireball.
Bigbadwolf: Wolves are larger.
Never Surrender: More military
If you're interested in Zeus, Master of Olympus check out my full review of it, here.