Just a tip to beat this game: ALWAYS click in the center, you don't need to aim, calculate the ball's moves or anything like this. After some point (level +5), this game is pure luck/random. Therefore, if you click in the center, you maximize your chances since the probability to have a collision in this area is higher. If you fail, start over... after couple tries, you will beat the level. You can beat the game in 5 min doing this.
The hard badge should be either an "impossible badge" or change to 50,000 meters (45k would be ideal). After 40k meters, the monsters take at least 3 to kill and the game becomes pure luck to find a potion. Although, it's a great game.
I really liked this game, great puzzles. Too bad this game is so underrated (avg. 3.83). Probably because some maps are really challenging and some people don't like challenges. Then, they underrated this game just cause they can't get an easy badge.