So here's my thing.
I have a Level 6 character that is normal. I already made an Super Idol (N?) card of the same character, but she's level 1. I'm just not sure which I should keep. Obviously the higher level card has better stats, but I would need to fuse to get her to Super Idol again.
Also, is the only way to level cards by feeding them other cards?
1. well, as you probably know the max lvl is different from normal card and fused Supuer idol card. So with your lvl 6 card, you would still need to fuse with another same card again to get max lvl. So just keep the already fused Super idol and feed the lvl 6 one.
2. yes the only way to lvl up cards is by feeding other cards.
Also some thing people might not know about:
-When you do special practice(fusing the same cards to make super idol)
Which one you pick first matters.(your base card)So for example, you have 2 of the same N cards, but one is lvl 10 with 25 bond and one is lvl1 with 0 bond. If you pick the lvl 1 with 0 bond as the base card and pick lvl 10 one as the one getting fused, you will get lvl 1, with 0 bond super idol. But if you do it other way around, you get lvl 10, 25 bond super idol.
-when you lvl up card by feeding, make sure you feed the same color. They give you extra exp.