Imported from Japan. These Sumo trading cards are based on the November 2016 rankings. Each pack contains 5 random cards. The complete set has all 42 top division (Makuuchi) wrestlers, 28 second division (Juryo) wrestlers, several up and coming wrestlers, and some wrestling action cards for a set total of 90. See the scanned checklist for details (which are in Japanese). There are also 10 different autographed cards included randomly across every few boxes (24 packs per box). Most of the text on the cards is in Japanese, however, the wrestler's English language name is also on the card for those of us who don't speak Japanese.
Yokozuna for this series are Harumafuji, Kakuryu, and Hakuho.
Ozeki are Goeido, Kisenosato, Kotoshogiku, and Terunofuji.
Check out this link for the Makuuchi and Juryo rankings from November 2016 for a complete listing of all wrestlers from the top 2 divisions.
If you are looking for a Harumafuji card, you need to buy from this series or a prior year as he is not included in the 2018 Rikishi set.