Final result: 1,237 players, 7 solvers. Congrats to the adventurers who solved it!

Here's the Puzzle.

I post the solution here to prevent ruining the fun of solving it. I suggest you try it again instead of reading it directly.
I won't post the link directly, but you can follow the steps and find it easily.
This topic is closed, if you have questions or want to say something, comment [here]((http://www.steamgifts.com/forum/ghXnE).

Welcome Quiz
You can find answers for Q1 & Q2 Here
As for Q3, UEFA is not a video game.
Firstly you have to know which country the develop team of Q1 come from. Secondly you need to figure out who's the hero of that country during UEFA 2012.
_

Then you'll get result to a mini Jigsaw puzzle. Solved it you'd get a 8-letter string.
If you don't know what to do next, read update1&4, it suggest you to try Itstoohard.com

Game Identification
1.Metro 2033
2.Penumbra
3.Amnesia
Q1~Q3 are easy, so I post the answers for them. :P

For Q4, it's not Zuma Revenge, although it's the same god. Check update3&5, there's another Zuma, and you don't have to buy it, it's a FREE one.
For Q5, check update14, what did Google suggest? Although it's unbelievable, try it!

After that you'll find a life picture.
Analyze this picture, if you find Rick Roll or Troll face, remember update11? Try another way.
The previous quiz's result is a hint: I have heard that someone hates binary thing. C'est la vie.
Use notepad open it you'll find a wall of 0s and 1s, see?
It's hard to ignore update2, it suggest you can't translate the whole binary thing together. There's two parts waiting for you.
Don't forget your friend on update8.

Part One
01->01
binary->HEX

Try HEX->Base64->Text, remember update2? Then try to fix it!
update6 suggest you should fix the HEX, then update15 means
ab->ba

btw, there's another way to get it. Some guys notice there's some characters doesn't belong to Base64, actually it's because the HEX being modified. You can change the [ { things to right letters and get the same thing.

Base64 twice
Rot10

Don't try to brute force the designer, it's not necessary and mostly because you probably using the wrong list.
Read update7 then find out the special one, there's a non-videogame lying there - and you try to brute force it with a video game company list...

Part Two
binary->HEX

Try HEX->Text, what do you get? It means stop.(update11)
update10, check the group announcement here is the big hint.
You'll find out it's too easy, because the answer is not important! The question is. Q4 is weird because the lower case v, and Goo gle is your friend means you should use goo.gl
There's a QR code there, people often hide QR code as thumbnail, this time I did it in the opposite way. You'll get a blur pic like a table.
btw, for Q4, Yes and No are both the right answer. xD

update13, check the links and you'll find the group's abbreviation is nonsense, that's it! Then update7 suggest that you should use goo.gl
Then you found a wtf pic, if you notice there are 26 lines there, just simply wrote a program or use notepad to find and replace the HEX code (93 69 73 11 53 25 14...)

If you don't know, it's OK, there's a lot of hinceptions waiting for you.
Firstly, update9: Zodiac, it's not about stars, the movie? Not exactly, it's about the method this series killer use to encode his message.
Secondly, remember the blur table? It's hard to recognize, go to my profile and decode the things there. First one is nearly impossible, try second one: It's like a morse code but no space there, actually it's binary again!
Decode it and apply the result to goo.gl you'll find a wth pic, that's Zodiac 408 code table.

Zodiac killer use a method called Homophonic substitution to encrypt his message.
Then you should know how to use wtf.jpg deal with the non HEX code.

Now you got the whole message, just google it, two keywords would find the director's famous movie.

This quiz is used for checking your answers.

Final step, combine your answers you'll get a 5-letter string, that's the private giveaway code.