i just didn't like the mechanism to grinding many heroes

The gameplay of this game is simple and easy to understand. Tap to attack, swipe to dodge. Each adventure requires passing dozens of levels. This will include bonus levels and Boss levels. You can choose from one of three random abilities each time you upgrade. Through different combinations, the battle will have different fun. There are two points that need to be improved. First, the ultimate skills are too few, there are only two ultimate skills to choose from at the beginning of the game. Secondly, there seems to be no other way to get new heroes other than topping up, and I can understand the developer's need for income. However, providing at least some of the heroes that players can get from within the game would be much better than the current one hero only.