Collect all of the Special Item Collectables and place them in their required pillar to unlock certain special Challenges in the game.

Axe Extender Challenge 4 - Collect all Priest's Amulets
Gauntlet Extender Challenge 4 - Collect all Emperor's Coins
Sword Extender Challenge 4 - Collect all Titan Tablets
Sword, Axe, Gauntlet Challenge 4 (Choose your Ultimate Weapon) - Have All
Special Item Collectables collected