Babe cards, but look Wiki first. Most babe cards are at 6.2k max SED (R, except Airu who is 7k) and 11.7k (SR), and a lot gain less SED beyond lvl 80.
Unless you want to fap or go PVP, Moe cards doesn't have a good gain after lvl 60 (Runa, Hiyori and Sora are the only good choices for PVP, unless you got some event rewards).
And also, i've noticed that R cards could be upgraded with SR wildcards... is it worth it?
Act like a R wild card over them. Only sacrifice wild cards on EG/perogambit events, if you picked a slayer card and you have no choice (to boost her).
P.S: i'm supposing your level is below 50. Beyond 50 is easier to get R wild cards (farm pero in GHQ or waste a lot of N gacha tickets).
Give one F2P game to a Korean: He will turn it in a P2W (pay to win)
Give one F2P to an American: He will turn it in a P2F (Pay to fail)
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