Mario Bros. Featuring Karnov!! is an unlicensed (Unl) NES game, suggesting it is fan-made or unauthorized. The title indicates it attempts to combine elements from the Mario series with the Karnov franchise.  Due to its unlicensed nature, details on the creators and gameplay are limited.  It's a testament to the enduring appeal of these franchises that fans would attempt to blend them into a custom creation.

Mario Bros. Featuring Karnov!!

Mari - Ayami - Luka no AV Poker (Japan) (Unl)