Having enough money helps you to win the battle more easily by sending reinforcements whenever you feel you will lose the battle. However, you will not get much money from the generator that’s why I’m telling you to level up so that they able to the generator as much as they can. You have two options to get in-game money, the first one is to buy with your real money, and the second is to get from Cents Generator, which is the best option.
Upgradation of characters requires money without them, you can’t upgrade. Moreover, you can only carry 10 different cats in each stage, and they are capable of defeating other animals if all of them are upgraded to level 10. Apart from this, everyone has a unique power, and you can increase their strength as well by leveling up. The Battle Cats game is full of different characters there are more than 300 cats, some look funny, and some look like a devil.