You don't have to spend real world money to get a high level monster in Epic Pet Wars.
If you follow this simple strategy, you will have a pet with a level in the 50's within a couple of days.
The most important thing you have to do in Epic Pet Wars is to collect as many yen as possible ASAP! Allways spend each remaining yen in investments.
You allways have to buy the weapon / armory / accessory combination with the highest defense value possible.
If you are out for a fight allways prefer an opponent without armor to one without a weapon.
When you use items to restore health points in a fight, use items that increase your defense points at the same time.
Make use of spells that decrease your opponent's defense points in favor of spells that cause direct damage to its health point.