I got this idea one night and knew I Needed to draw this first thing the next morning!
I was thinking about how all the Pokemon Pirates I have made use a Duskull Skull as the universal symbol of being a Pirate. Of course it's meant to be a Jolly Roger but there are no Humans in this setting so I had to use some other Skull and Duskull has a very simple cartoon Skull face so seemed like an obvious choice...But I wanted to come up with an in-universe reason why all these pokemon use Duskull as the Symbol of being a Pirate. I first thought about making it a oddly powerful Duskull, but I couldn't find a way to make it work...then I thought..."Who else would use the Symbol of a Duskull to their advantage...maybe a couple of Hoenn Psychic types?"

Solrock and Lunatone use their Psychic powers together in order to control a mech body made from the broken scrap parts of multiple Shipwrecks. They are the Origin of OLD nautical legends, seen as more of a myth and a monster than a Pokemon. Rumors have it that they are guarding some sort of vast treasure hoard accumulated from all of Ships which frequently crashed upon the rocks of their island, Others say there was already some hidden treasure on this island and the ships of those foolish enough to pursue it have only added to the pile. Whatever it is, it must be pretty important and valuable to need a guardian. Getting close to it's land by boat is nearly impossible and if you are even able to get close enough then you'll have to fight the Shipwreck Skullem! (Skull + Golem).