What is this game really?

This game popped up as a recommended game, so I tried it. I got stuck within 2 hours for 7 days straight. I even spent a little money using Google Play Points, but even when I force myself to collect gems, I get stuck within 2 hours every single day. After 7 days, I hit a wall with the stages I progressed through with minimal spending and can't go any further. It's like they're saying, 'Don't play unless you're a whale.' Typical Nexon game. Aggressive monetization, just like their flagship game, FIFA.