This is increasingly becoming a Pay2Win game. The developer does not encourage skill cultivation, but would rather u pay your way to higher levels by buying advanced aircrafts. Even on PVP, the algorithm is such that after a round or 2 of winning they'll start consistently matching you with much higher-level contestants. They orchestrate your PVP losing streaks so that u'll feel inadequate & desiring for gem & purchased ships. The same goes with the ever harder Trials/ Boss rounds. Be warned.