As for religion, the gods are not easily calmed as in the previous games, where building another temple or throwing a festival did the trick. The gods in Zeus can't always be pacified, and in fact, pleasing one god often means irritating his or her rivals. The annoyed ones will send their pet monsters after your city, such as Poseidon's Kraken or Ares' Dragon, or they may come to curse and destroy your buildings themselves. You defeat monsters by summoning heroes specific to each monster, and keep angry gods at bay by invoking their rivals through the building of sanctuaries. Gods will also ask you to find things for them, which requires you to summon a hero and send him on a quest.
Sanctuary building is similar to monument building in Pharaoh, but with considerably less hassle.
There is still a challenge in getting the required materials, but not the ridiculous waiting periods, and there's often more flexibility in how many sanctuaries you build and to which gods. The adventures themselves are slightly different in structure to Caesar and Pharaoh as well. While those earlier games took the player on a journey through history, Zeus doesn't even attempt to be historically accurate. The adventures are ordered from easiest to hardest, but players can try any adventure at any stage. Furthermore, each adventure consists of several chapters, so unlike the older games, players can't let the city be on the edge of falling apart just to satisfy win requirements, because the next chapter requires that city to be back in operation.