Board Thread:Card Unit Builds/@comment-25125095-20140729115019/@comment-25099139-20140729120938

Using medals to get more arcana is the only effective way, that I know of at least. If you need more medals, amalgamate every metal slime and gold girl you get into medal girls and medal all r cards and useless/ repeat sr cards. As with almost every issue, the solution is too fight more archwitches. It usually takes me an hour or two to max a hsr since I have plenty of sr cards to medal and I always have full medals. If you have the time, you could go for arcana def+ and arcana att+ ( 500 stat increase instead of just 50 ) from progress points and gold chests during the key events, although racking up progress points requires lots of time and keys require lots of time and lots of archwitches, so they aren't to effective. Sorry, seems you'll have to grind it out most likely :( Good luck getting more cards to medals and/or arcanas! ^-^