Originally posted by SnazzySmurphOkay, within the game world:
Lies...Let's try this from the opposite end.
YOU describe a Mimic. sly
A mimic is a creature who's origins are not fully understood. Some suspect it came to be when a wizard was experimenting with a better way to store and keep their treasures secure. Now naturally the same magics that created a bag of holding (portable pocket dimension, you can put anything into the bag so long as it fits into the opening) would have been used to be able to store more items in it at the same time. Making it more durable would have been a neasy enough spell, magic resistence and a better durability so that most weapons would be ineffective at compromising the treausre chest's structural integrity. Making it be able to fight back would have come next so that the people trying to get into the chest wouldn't be able to just sit there and figure a way around the magical enchantments on the device. But haviong it attack the would be theives wouldn't be enough, an animal level inteligence for it to try and survive and get away from the theives would be expected. Of course there are other ideas like trap spiders who lie in wait and lure its victims to it. Trapping a person within the mimic would keep them from being able to escape.
Other theories go that they were demons, changlings or shapeshifters bewithed to remain in the form of a treasure chest with some of the previously mentioned enchantments on them.
Basically everything you've been describing for "The Luggage" sounds like a mimic.
It looks like a mimic, it acts like a mimic, it sounds like a mimic.
Chances are The luggage was based off of a mimic.
In any case, Wolverine wouln't have a chance against a mimic or the luggage. In the RPGs you usually have a magic weapon with you which increases your chances of dealing... 1 point of damage per attack to it. Certain weapons like those non-magical usually are totally ineffective gainst them.