I propose that when you have this chest on your ship it transforms you and your crew into skeletons and your ship into a ghost ship.....but as long as the chest remains on your ship you get an increased chance of finding other high value chests. It makes everything you do more valuable but it also puts a red flag on you bc your a big unique ghost ship for everyone to attack and try to take the treasure from..... I'd also say the chest has to be removed from the ship without sinking it. If it sinks it has to be found again.
Thoughts?