Board Thread:Question and Answer/@comment-27036342-20160202193206/@comment-5665420-20160202215248

Someone in alliance forgot one yellow arcana somewhere in evolve for Hiraga, I think it was in UR+UR stage and the effect was 1k soldiers less. It should be less dramatic if you skip it in earlier phases but yeah, better do it properly.

Also, yellow arcana drops relatively often from witch hunt. You might need to buy a few times with medals but you should have enough in your inventory after a few events.