Okay, did my best to make sure this hasn't been done.
Set Up is Ra’s Al Ghul , latest plan for world conquest requires the resources of Latveria. Therefore he plots to overthrow Doom. Who emerges as ruler of Latveria?
Ra's Al Ghul, can take all the prep time he needs before he makes his move (but no he can't wait 100 years for Doom to die of natural causes).