Power-ups
You can only use a limited number of power ups, based on your level. Always have Heal as your first power-up, then use Attack or the Monster power-up after you have unlocked a second slot.
Stats
Each time you gain a level, you can spend attribute points to improve your hero. Prioritize Attack, Magic and Defense as your main stats to increase, and keep their base value four or five points ahead of the others.
Various Tips and Tricks
You have only ten lives to begin the game, and whenever you lose a life you have to wait for it to return.
You can watch a video with an advertisement and regain one life for free. Or, you can go to the date and time settings on your phone or tablet and set the time ahead by 20 minutes per life.
You can log the game onto Facebook and send lives back and forth with your friends.
You'll get keys as you battle, and the keys are used to open three different treasure chest. Save up three keys so that you can open the big treasure chest each time. This one will contain the best equipment by far with the greatest statistical boosts compared to the stuff that you'll find in the cheaper chests.
Speed is key here. Knock out combos as fast as you can, and use tricks to score massive amounts of points at the same time.