Select your hero, There are no ability difference between each hero, just pick up your favorite.
Make your decisions, Usually start with defeating monsters. You can get one star when you beat a monster, and choose the less damage one first. The stars can be used to enhance your ability. Under normal circumstances, I suggest you upgrade the defense first.
This is equipments sold at shop. After you collected enough coins, you can try to buy some equipments.
Swords always add attack as long as shields add defense. Buy the most expensive one first, because they have bigger capability/price rate.
After complete some events and enhance your ability, the devils is about time to appear. Try to develop the strategy to defeat the devil. Maybe enhance your attack, defense or wait, do not forget to increase your life sense you will game over if you don't have enough life. Be remember that victory condition is beating any one of devil! So pick up the weak one, and try to defeat another.
ps. devil have difference background color(red) to normal monsters(black).
Congratulations, you finally successfully complete the game, but do not get to excited, this is not the end.
After win the game, you can enter arena and challenge the past heroes. Try to defeat you own heroes you've developed is an interesting experience, don't you think so?