10

http://ten.reluctantsnake.de/index.php.png

Edit: I just slightly changed one part of the puzzle, as some thought that a lowercase L was a 1.
Some hints might be dropped a day or two before the giveaways end, but a good amount of you have already found all the giveaways. So I don't want to make it too easy for everyone else.

Edit #2: Seeing as so many have solved the puzzles, I will not drop any hints. I feel like that would not be fair to those that didn't need them.
I will add the solution once the giveaways are over.

Edit #3: The giveaways have now finished. I'll send out the games and will add a solution to the puzzle in a bit.

Solution

• Follow the link (http://ten.reluctantsnake.de/index.php.png) and remove the .png at the end of the URL.
• Click on "/ten/" and it will take you to the first giveaway (God of War).
• The /-1/ is a hint that you have to change the url from http://ten.reluctantsnake.de/ten/ to http://ten.reluctantsnake.de/nine/.
• Save the image of the zipper and open it with a file archiver like 7-Zip. There's a txt file inside with a link to the second giveaway (Psychonauts 2).
• http://ten.reluctantsnake.de/eight/ The key is "994" (taken from my username). Add that key to the url (http://ten.reluctantsnake.de/eight/994/ to get to the third giveaway (Wasteland 3).
• http://ten.reluctantsnake.de/seven/ Just complete the jigsaw puzzle to access the giveaway (Devil May Cry 5).
• http://ten.reluctantsnake.de/six/ Decode the string with a base64 decoder. If you look at the page source, I have added one as a comment. (Pillars of Eternity II: Deadfire - Obsidian Edition)
• http://ten.reluctantsnake.de/five/ R to L means you need to read the giveaway code from right to left. kZDh4 -> 4hDZk -> https://www.steamgifts.com/giveaway/4hDZk/ (NieR:Automata™)
• http://ten.reluctantsnake.de/four/ Translate the binary to text to get the giveaway URL. (Thumper)
• http://ten.reluctantsnake.de/three/ (Fallout 4: Game of the Year Edition)
• http://ten.reluctantsnake.de/two/ Solve the Nonogram. Y0Vbp -> https://www.steamgifts.com/giveaway/Y0Vbp/ (Shovel Knight: Shovel of Hope)
• http://ten.reluctantsnake.de/one/ Caesar cipher with a right shift of 23 (as in the Wikipedia example) gets you the giveaway link. ZmnKe -> CpqNh -> https://www.steamgifts.com/giveaway/CpqNh/ (Rogue Legacy)
• http://ten.reluctantsnake.de/zero/ (Borderlands 2 & Age of Empires IV)
• https://www.steamgifts.com/giveaway/Yjodr/age-of-empires-iv The link to the final giveaway is hidden in the giveaway description. You just have to look at the page source. (Fortix)

View attached image.

View attached image.