This achievement is for earning 500 hits with henchman that are tied with the "Keikain Onmyoji". There aren't many cards in this category, that said it will be slightly tougher to earn this one. These cards are under the lighter "yellow" category. Not to be mistaken with the gold category which contains all of the gold cards. You can earn these hits across all modes excluding the practice and tutorial modes.
It's advised you do this after completing story mode as well as the challenge mode so you have as many cards as possible. The only two I used for the hits were Ryuji Keikain card and the Yura Keikain card. If you need information on who these characters are, use the wiki below.
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