The mute, bumbling invasion from Neptune was manned by one of these fellows. It is impossible to tell one Neptunian apart from any other, and that is not a racial slur; they can't do it themselves. You would think a collective superconsciousness would afford them a tactical insight unbeknownst to lesser races. You would think their technology would send the innermost worlds into a trembling fear. You would be wrong. That is because of their need for two nutrients.
Two words. Rojium. Pantium. A Neptunian must constantly balance it's levels of these two substances to maintain an equilibrium. The Roji-Panty complex, like maintaining the PH balance in a saltwater aquarium, is well... complex. In gameplay terms this equates to rotating attacks that leech or expel the various vapors. So far nobody has figured out how to play one. Four beta testers have been reduced to gibbering vegetables by even attempting to master the Neptunian move set.