Elemental damage helps. It's not as effective as a synergetic squad, but 1-2 girls of the right type in a squad do make a difference. So if your choice of girls is still limited, preventing you to make squads that really fit together, then customizing the squad to the damage type you expect is the next best thing, but will require regular changes to your units.

Mono-type units work great when you're entirely sure that you'll only encounter targets with a weakness against 1 or 2 types. I think it's the 10-? and 11-? maps which are mostly weak to hit-type for example?

But, as Kringley said, you get all these different manyus. Use your manyus on girls of the right type (or color), level all the girls you actually use (but the ones in your first squad a bit more), and you should generally manage to get through the maps.

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Originally Posted by Rupturez

Im having insane luck in this gacha, im already at reset 7!

Guys a mandatory advice, when you summon the secret stage you can run it as much as you can for 5 min. Make sure you scroll with your mouse like a madman during the boss fights because it speeds up the animations considerably! You finish faster so more runs!

I never noticed the scrolling sped up the animation, but after testing, this only seems to work if you have fights play "fast" anyway (on the top right corner, there's a button that should be lit green).
*Not* having autorun activated and just spamming the big "next" button to move your girls is also obviously mandatory.
Now I just have to figure out how to speed up that results screen at the end of the map, that's what's taking most of my time.