There's a a lot of talk about the Black Order coming into the MCU and in a recent interview with Terry Notary (he plays Kong in Skull Island) he states that he's going to be playing the right hand man to Thanos could this be Corvus Glaive ?
Corvus Glaive is a member of the Black Order along with his wife Proxima Midnight and I know we don't spec much on villains but this comic is really cheap and could be worth a punt. His first app is Free Comic Book Day 2013 (Infinity) #1.