a Swashbucklin' is a fight in a pirate talk. You know, like a boarding.
The card pretens to simulate a boarding where all your creatures board the "enemy ship" where are the opponent's creatures. So there are 50% of chance that one of your creatures hit one of the opponent. That opponent's creature is also randomly choosed and if it's quinted or burrowed, nothing happens.
I think it suits well in the entropy team and also in the pirate theme.
For the balancing pourpose, it's like a massive gravity pulls that has 50% of success each one for each creature.