Evgeny Gradovich
The Mexican Russian fighter out of Oxnard who holds the IBF Featherweight belt would prove a tough out for Abner Mares, but it would be a fun fight and definitely a fan favorite.
This match could be held in Southern California, most likely the Stub Hub Center where all the best wars take place.
Mares might be a bit timid to take this fight, with Evgeny Gradovich being a tough champion who has a strong chin, but devoid of KO power. It would be a great fight.