3* only from level 20 Traning Camp

Sure thing. At least TC20 is free, so you can keep doing that even if you’re not spending. There are a lot of people who are F2P or C2P, and actually seem to enjoy the game more because they’re not feeling upset it anxious about the money they’ve sunk into the game. If you’re feeling burned out on spending $$$ on the game, give F2P a try and see if it works better for you.