Hopefully I can get some insight from other DM's on how to deal with this particular player.
I have a member of our group who has optimized his fighter far above and beyond any of the other 3 players, all of which were built around a more thematic and role play design. At level 12 the power disparity is more then a little significent. During battles he almost always kills anything before the other players get a chance to act, and most of the time the other players just have sit and watch him during combat. I could certainly up the stakes when it comes to encounters but in order to effectively challenge him, I would be required to put the rest of the group in a situation where they are very likely to be killed by whatever it is they are fighting.
When talking to him about his character he simply states that "its not his fault the other players chose not to be the battle god his character is to become." And when I introduce scenerios that involve non-combat situations I am told that I am being unfair to his character and not allowing him to do what he is there to do.... Walk through enemy lines and destroy all evil. Which almost always ends up in an argument as to why social skills even exist in the game at all, and how we're wasting time finding our way around a situation that he could easily cut his way through. Adding to this his constant intentional manipulation and arguing of rules (of which he does not actually own a copy of) and general disregard for some of the newer players as "wasting time with looking things up" I'm quite honestly at the point of booting him from the group all together.
All being said, I want to be sure that I'm not just frustrated as a GM at not being able to give a game that is fun and challenging for all involved. So any suggestions on how I might be able to build scenarios that can satisfy his lust for blood, and the others desire to play a game less focused on combat?