The bonus game in ‘Skull Duggery’ is ‘Booty Bonus’ and is triggered when you get three or more of the bonus symbols on an active payline. Once that’d been achieved you see five shipmates on the deck of their pirate ship. Your decision is to select one of them to be chucked into the sea. You get a cash prize for that and how much you receive depends on how many bonus symbols triggered the Booty Bonus. If it’s five then you could win as much as 3000x your line stake.
The way in which this bonus is triggered means it’s best for you to be activating as many paylines as you can afford.
There are definitely a lot of better pirate games that you can play. It is one of the older Microgaming slot games so the basic look is understandable. There are still some good wins to be had here but the rather brief Booty Bonus isn’t the greatest of bonus games.