Marshadow is a ghost of someone killed at the Pokemon equivalent of Pearl Harbor i.e. a Victini counterpart
Wimpod2 is a giant isopod mixed with a samurai. Maybe based on villains from Japanese superhero shit like Super Sentai?
The diving bell spider is a diving bell spider mixed with a scuba diver.
The other thing is a crown of thorns starfish anthropomorphized as a princess with a crown. It and its evos also combine aspects of other echinoderms (such as sea urchins) as well as sea anemones.
