Originally Posted by YoshiEnVerde

Exactly. Once you reach costs of 4 or 5, the time you'll need to get those cards maxed will be too much to be worth it. By then, the lack of cards will be worse on your SED.
The idea is to take advantage of the earlier stages cheap costs to max as many cards as you can. Stage 1-3 is just a particular case where the relation between sta cost and exp/pero/spin rewards is very favorable to the player.

Just try not to stay too long on that part of the game. You might get a better SED than other people in a few stages above you, but in the end you'll ack a lot of cards (unless you try to get them all from gacha, and even then there is a dozen that's not availble anywhere but by playing their stages, or BA and GHQ)

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The main idea is that reaching lvls above 30 while still in the low stages will allow you to throw around hundreds (even thousands) of spin tries every day. That means getting hundreds of card level-ups a day.

Thanks a lot.. that's really helpful