Depending on the people I am playing against, there is Quakeworld deathmatch, Team Fortress Classic, Left 4 Dead, Counter-Strike:source, Diablo II,,. I can not pick one game and say it was the hardest. This because I play multiplayer games, and the skill of the other players is a factor. I can say the most intense was Unreal Tournament, and Quakeworld. Between those two, quakeworld Deathmatch was the most intense online, multiplayer game I ever played.
Don't you hate it when people immediately kill your thread with a pointless answer? Anyway, I would say EVE due to its massive depth and steep learning curve.
I think the world`s hardest game would be this one. Check it out and let me know which level you reached so far
DAMN!! i just played that link game which you gave.. That's called HARDEST GAME MAN! I done 3 levels. but 4th is toooooooo hard.. can't done.
Starcraft(could be counted?). This game is a very good game and most balance for each players. The game system is not hard to learn or play but challenging from player skill. There're many rank from newbie to pro players that lead to super easy to the hardest game you ever play! This is the most competitive game in the world.