Originally Posted by CrustyDirtDemon
Im having the same issue, I have all collectable cheevos, however I dont have the level 10 challenge...WTF...Hmmmmm...PLEASE HELP!!!
Pretty sure the last one is unlocked when you have gold on all others.
OR.. Have you picked up the Ceramic Rooster in the Laboratory? If not... go to the Laboratory and theres an Enigma Keypad down a small stairway. Inside is a Ceramic Rooster which unlocks one of the Challenges. This is the one most people miss.
Originally Posted by Cade91
How do you unlock challenge 3, 8 and 10? I have got all collectibles, the rooster and finished the game!
As far as I know, you only need the collectibles (incl rooster), and then golds on previous challenges to unlock them all. I didn't have to do anything special. If you have everything else, it's very strange for 3 challenges to be missing.