[2021] Incorrect reward for purchase

This is within the intended results, not a bug. “May” means sometimes, not guaranteed. If you already own all the Legendary Mercenaries, it chooses a random one for you and grants you the basic portrait for that Mercenary–if you already have that portrait (like you would for any roll that isn’t the pre-purchase Mercenaries), it converts it to the 100 Coins.