What's the hardest game you ever played?

I'm gonna go with Wings of Vi. I made it to the last part of the game and took a "break". That was quite a while ago :p

I would have to seperate by skill,RNG ,and enduring-that-crap^^
RNG:
When it comes to a brutal RNG, then a lot of the old AMIGA/DOS Games were brutal, wiping you out with one event.
(I especially remember some of the german "economy simulators" having events that made you bankrupt at once out of the blue. Oh, and of course i did not have a handbook, there was no booking of income/costs, no descriptions etc :) )
Dwarf Fortress and unreal worlds also tend to have brutal events.
Brigade E5-a great game but brutal RNG..if you take cover, and only your head sticks out, guess what happens...

Endurance:
"Godfather" made me wanna strangle myself..time to conquer a stupid tiny pizza place AGAIN.AND AGAIN ^^
All the games that have non-stoppable cutscenes BEFORE a boss fight, so you have to watch and listen 2 minutes over and over if you f* up the boss...
"Boling point"- couldnt play 10 minutes without a servere bug or crash. Too bad..
Oddly enough-minecraft: So youve spent two hours building up finally whatever-tech-mod-machines youre using? Have a creeper. All destroyed. Byebye ultra rare ressources XD
99% of all games you get for free...cause they are mostly BAD, BAD, and have bad gfx as a surprise gift.

Skill:
By now, every single game that has platforming/FPS parts, because i am getting old and slow.. especially noticeable when trying multiplayer :/

I wanna be the guy gaiden... that game's designed to troll you xD

Polybius

Bit of a complicated question for me. Personally, itd be Dark Souls, but purely because Im just not very good with controllers. I see the fight, I know what to do, but Im just not used to controlling a camera with a joy stick and more often than not, I end up staring up into the sky or at the floor instead of the boss. I managed to get up to that weird dragon thing in the sewer (forgot its name) before I decided to take a break.

As far as difficult as in challenging gameplay, Id have to go with probably Crusader Kings 2. My friend makes Youtube videos of his gameplay and theres just so much infortmation to take in and remember on top of the politics/stats/gameplay that if he wasnt explaining every step of the playthrough, Id have been lost 5 minutes into his first video.

Super Hexagon hands down wins here.
It does say " game over" in the sweetest way.

Hm, I think there are a lot of possible choices in my Steam library alone but since I finished most of them I probably should choose the one I did not: Teleglitch. And I really tried to play through all ten levels. But you are dead in a mere second even while paying attention. Yet, I can't say it is unfair in that regard.

And another really hard game would probably be Snake, Rattle n'Roll for the NES. I wonder if anyone knows that one. I strongly suspect the final level of the game is only beatable in co-op mode and I've only completed it one time.

Russian roulette with pistol xD

Battletoads (NES)

I Wanna Be The Boshy!

Real Life. You are alone, Difficult depend where you were born. Most of the people care only about money and themself.

Xcom terror from the deep - especially if one of your goals is not to let any of your men die!

Skyroads was a hard game in the old windows 95

as said before, life :P

Real Life....

Pros.
Amazing Graphic and Physic engine, every encounter/ conversation is unique, no limitation to your choice you can do anything ;)
You newer master it ;)

Cons.
No savepoints (how many times you want back to old decisions and change them eh...) , when you try cheat can cause Bad End (example cheating in lowe can cause knife in your back ) , common is that other players will try cheat you and steal you items ;0
No respwn option and start new game this sucks you are allow only play once ;0
Achievements are broken, sometimes you get it for nothing other time you do a lot of work and do not get any :/
A lot of grinding to get a money :/

If rom hacks count it's Kaizo Mario. Otherwise Battletoads for the Snes. Found this even with savestates hard.

zelda 2 the adventure of link

Risk of Rain. But so satisfying.

Alien Isolation...

Almost any platformer game. Mario Brothers all the way up through Super Meat Boy. Fast precise timed jumps and double jumps... bleh. I can't beat any of them.

but I enjoyed Mr. Bree+ the most.

To those of you saying real life, please stop it. This is for games Not real life. The joke is old.

Starcraft multiplayer, Starcraft 2 multiplayer, OpenRA multiplayer, Company of Heroes 2 multiplayer, cant win, cant win at any strategy game online basicaly, but then again, i dont win anything online, mostly i dont anyway's. Oh and i never beat Battletoads on Sega Genesis, or Flashback, or Zero Tolerance, or Mortal Kombat 3 (f*** you Shao Kahn), and...just alot of games realy, but i have beat alot too, theres just alot to mention.

Commandos 2