If you're thinking of downloading this game, don't. I've been playing for several years, and it has gotten progressively worse about needing to pay to win. I only play as a time killer and have never paid a penny. I used to get stuck on a level, but now even the basic hard levels are almost impossible. Every update is worse and worse for the player. They don't just add levels. They also reduce rewards. This is the only game on my phone and I regret getting it!!