A tip if you're starting out a new account, although this is probably common knowledge to you experienced folks. It's more to help out noobs like me, but when you're starting out and low in levels, DON'T FINISH MISSIONS.

Do the reissue events, and retreat right before you win. In this way, you get the mats, while getting low exp so that you can use up most of your stamina before leveling up. I'd do this until lv 15-20 or so.

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sorry for double posting, I can't edit my post =/ another tip is to evolve one of the level 40 starter 2* girls. Or, evolve another character, but anyway, you get 10 flower gems for finishing the tasks in the 9 panels, and one of the tasks is evolving characters. Another "hard" one is logging in the next day, so you'll kind of have to wait a day to get the flower gems.