Each level must be completed before you can progress to the next. You can replay any level from the level map to try and earn three stars if you did not your first time around. You must have a certain number of stars earned at each location on the map before you can unlock and proceed to the next location and set of six levels.
Using power ups is a great way to increase your chances of passing a level. You can purchase them with silver coins and with premium gold bars. They are available before you begin a level and you can stop the game and purchase more during the level. There are only a maximum of three power ups available per level and the type available varies and you will see a different three power ups available for each level. If you can afford them they are very helpful especially level twenty and above.
Energy can be regenerated at a rate of one point every thirty minutes for free so if you run out you can either purchase more with ten gold bars for five energy points or wait until you energy meter refills on its own. If you earn at least two stars from playing a level you will be rewarded with coins and one energy point.
If you have a Facebook account and decide to link it with the game you will be rewarded with forty premium gold bars. Tap on the Facebook icon on the game map or go into the settings menu to log in.
If you purchase a game boost for your level and do not use it you will lose it as they do not carry over to any other levels. Some boosts start automatically when your level starts and some you must tap on to activate when you feel it is optimal while playing the game grid.