Moa's nature and what kind of alien species it was(if he is an alien) is a mystery. He first appeared as mysterious hooded creature with black cape whom visage was obscured by shadow with except of glowing red eyes. When Commander Liebert resist Moa's influence and channeled his strength to blast Moa, Moa was revealed to be skeletal-looking robot, much to everyone's confusion.
However, it's later revealed that Moa was escaped death as the skeletal robot was merely a vessel. It then goes to create a crude body from objects that Freya took from Earth to kill Doraemon and co. in rage, but the body proved too large for the corridor that it forced to exit the crudely contructed body, revealing its true form as light green slime until Doraemon froze it, leaving it helpless and send it to the black hole to prevent more harm.
In manga, Doraemon proposed Moa as amalgamation of spitefulness within everyone's heart that somehow given physical form as slime-like entity. This idea supported with the claim of the spirit of Lian's mother whom explained Moa's supernatural ability to corrupt Liebert alongside his loyal troops and Freya (temporarily).
- Since the movie was created as parody of Star Wars, Moa is inspired by Chancellor Palpatine. Like Palpatine, Moa can be considered as evil incarnate in that story, has corrupted one of protagonist's father (in this case, Commander Liebert whom happened to be Lian's father) and mostly seen as hooded figure with immense powers.
- However, the major difference between Palpatine and Moa is Palpatine used to be a human whom corrupted by his own dark powers whereas Moa is grand manifestation of living being's negative emotion.
- He is similar to Agahnim, a main antagonist from The Legend of Zelda: A Link to the Past.
- In terms of true nature and origin, Moa is extremely similar to Erebus and Shadows from Persona series, The Negativitron from Little Big Planet 2 and the Orb from Marchen Awakens Romance series. All of them are amalgamation of negative emotion within all life in universe that given physical form and very dangerous because of their nature.