4. Vin Diesel
Perhaps a controversial choice, but certainly the biggest and most current name on the list, Vin Diesel could pull off the roles of Darkseid and Thanos. Diesel is a self-described 'multi-faceted' actor, which highlights his versatility and ability to potentially turn his acting hand to anything. He has a deep, bellowing voice and a muscular physique (which goes a long way to explaining the fact that he was a New York nightclub bouncer before his acting career took off), both of which could be very useful in playing villains in the mould of Darkseid or Thanos. Having played the role of Riddick in the Chronicles of Riddick film series, we've already seen Diesel playing a dark character with a very menacing pair of eyes, so it's not too much of a stretch of one's imagination to envisage how he might look as Darkseid or Thanos on screen.