So, Callisto has an ocean under it's surface, right?
Well, if there are squids there, then we should put squids on a planet that also has an ocean. 
Das right, PLUTO!!!!!!!!!!11
So, the squids are kinda like how the NPCs on Earth have variants, like how the NPCs in Brazil (you're going there) do stuff that the NPCs in United States of America (or USA for short) do. The yellow squids on Callisto will get replaced with green Plutonian squids. They are the ones mounted on ships, and the color the ruler of Pluto will be. The ruler's name is Franklin, and the city guard is Oscar.
The orange ones will get replaced with red squids, as a user thought the orange squids were red. So that's a neat reference. 
And finally, the purple ones will get swapped out with turquoise aliens. This is because they look good together.