The challenge to complete 100 wins with Mercenary is called “Morr’s Messenger”, and the image depicts a skull mask cosmetic.
Here’s the Kruber cosmetic hat that’s called “Morr’s Mask”, that features a skull mask, and the description writes about a mercenary company called “Morr’s Messengers”
So why is this hat not the reward for completing the challenge? The hat has been in the game for as long as I can remember, locked away in the game files, until only relatively recently surfacing in Lohner’s Emporium.
