Sonic the Hedgehog 1 & 2...

beaten Robotnik many times but I've never done it having collected all the emeralds, so technically I haven't beaten the game. First it's frustrating to make it to the end of a stage with 50+ rings (or to a checkpoint in sonic 2) without losing them all at some point. Then that bonus game is frustrating as hell, especially in sonic 2 (stupid tails).

Super Star Wars and the Contra series get nods too in the difficult category.

World Series of Poker, completing this game is impossible. Also Megaman is hard because there are no saves. I also find Moto GP 06 hard, it's hard to keep the bike on the road.

But I broke many a controller playing Ghosts n' Goblins on Nintendo. I eventually beat it, but the controls were awful for jumping.

There is no proof this guy is human, the video only shows the gameplay.

kk jk, but it's hard. 

Even at the highest difficulty setting Heretic II wasn't the most difficult game I've ever played, nevertheless I was forced to cheat for the only time in all the games I have played to beat its first boss, the Celestial Watcher: in that cramped final room of Silvermines, without any cover, I wasn't able to stay alive enough to kill him.

Perhaps I missed something obvious, as I didn't find on the net very much people having so much difficulty to do it...

Excluding this mishap, the most difficult games I've  played are, well, regarding fights perhaps most good FPS offer adequate challenges, regarding RPG, sneak'em up and similar, the Thief series, Fallout 2, Deus Ex and Planescape: Torment, where I must reload very often, as it's very easy to screw things up.

But the most difficult to finish actually for me is Morrowind, I've fallen in the vicious circle of exploring all and doing all the quests, so after a while I got tired, suspended playing it and now I find it difficult to continue playing it, I've lost the thread of what I was doing

People will probably laugh at me but oh well, i finished GRAW on normal, i played it on hard and to this day i have not cleared the first real mission. gears of war was insane when you play it on insane, as much as i felt like smashing my xbox COD2 and 4 on veteran are fun-hard, but i'd probably say Shinobi is the hardest game i have EVER played in my life.

all FPS games for ppl with motion sickness are hard and unplayable.
my friend got too dizzy and vommited after 5 minutes of counter strike long time ago lol

^ under this point of view,i should add Mario 64 & Goldeneye
The memories alone make me vomit{again :( }
Sorry,just one minute........................

"Werewolf" on NES. "Nigh impossible, say I!"

The Goul's and Ghost's series, Viewtiful Joe (its like every difficulty you beat you unlock another harder one! I HATE YOU LEO), Mario lost levels, I suck at the survival horror genre so most Resident Evil games and Silent Hill, I have no sense of conserving when it comes to games so I run out of everything, lots of NES titles were really hard, this one version of Mario I downloaded which someone made themselves was infuriating because of the difficulty, there is a few GB and GBA games that made me so mad I took them out of the system when they were on and threw them at the wall, Mario Kart was one but that was when I was on 150cc and trying to get either perfect in points and getting hit with something at the last minute or track times and messing up.

"Mario Kart was one but that was when I was on 150cc and trying to get either perfect in points and getting hit with something at the last minute or track times and messing up."

No kidding, I hate how Kart cheats to beat you at the last possible moment!