There is this encrypted mail titled ’D.R.P. Mail” in Crysis 3. It is encrypted and you have to play a mini-game to unlock the contents of the mail. The email is revealed to be from “M6”, and contains “rot hex rev rot 120234655564 15 142565543502N584N56504R4N5
 
If you put the string of characters into a ROT13 decoder, it gives you “120234655564 15 142565543502A584A56504E4A5”. Reversing the characters gives you “5A4E40565A485A205345565241 51 465556432021”. Entering the reversed string of characters into a hex decoder gives you “ZNVZHZ SEVRAQFUVC !", which turns into "MAIMUM FRIENDSHIP !” when entered into the ROT13 decoder again. I am not sure why the “x” got replaced by an “@”.