With the Needle, all "soft armours" can be turned back to half of used materials, rounded down to the nearest whole number.
In other words, the Needle gives 100% more XP from crafting armours, assumed that players only craft the mask (in an even number of materials).
Below is a table of materials' XP with needle. At 500 kills of each snake, bat and bear, one should have 100,000 XP, which is insignificant. Due to this, the Needle seems to be used for removing redundant armours rather than giving bonus XP.
*Note: expect a bit less if including armour parts from drops.
|Materials||XP||XP at 1,000||Average kills at 1,000|
|Snake Skin||20||20,000||500 snakes *|
|Bat Skin||40||40,000||500 bats *|
|Bear Fur||80||80,000||1,000 bears|