|This is the 'costume' that Laverne picks up while in the future that is dominated by Purple Tentacle (I won't tell you how she gets it cause that's a puzzle in the game for you to solve :P)|
It's basically a tentacle costume, but with white and red stripes with 2 blue 'suckers' on the front. She wears her normal costume underneath.
From the looks of things, the hardest part is going to be making the tentacle itself and getting the stripes to line up vertically. So all of it, basically.