Never neglect to keep your cloning center upgraded. Throughout most of the game, this building will serve as useless deadweight. However, if you get attacked by a strong enough player, your hero might end up being killed in the battle. You only get to keep a fraction of their hero experience, and the higher your cloning center level is, the more experience you will be able to keep.
Upgrade your radar because it will sense when you are getting attacked. If you are being attacked frequently, however, you can also go to the world map and see other players’ marches right there on the map, which essentially show you the same thing. You can use these to your advantage to prepare your city for an attack or to call your troops back to the city.
Another use for something like this is to launch a pre-emptive retaliatory strike against other players. Notice them marching towards you? Send your entire army over so that they can attack the attacking player’s city with no troops to worry about whatsoever (unless they only used their partial army). They’ll either see it on the radar and pull their troops back, or you’ll completely maul their city.
If your defenses suck due to previous attacks and you don’t have any time to build them back up before you get hit, pull your army out of the city and occupy a wild or some blank space until they’re done. Make sure your hero is on that march as well. Then send your hero and your army back to the city after the attack is done. As long as your storage bunker is at the highest available level, your losses won’t be too big.
Want to beef up your alliance quickly? If you are going to purchase gold, make multiple small purchases rather than one big purchase. Each purchase will send a prize to everybody in your alliance, so flood them with prizes and not only will they be highly appreciative, they will have more items and resources (and other goodies) to put to use.
Make sure to log in every single day that you play the game in order to get VIP status for a limited time. The more consecutive days that you log in, the more time that you get, and the better your VIP benefits will be.