He has appeared in most of MarioMario54321's adventures, as well as in other videos like Starman3's birthday video for MarioMario54321, to welcome him to the castle. In most of the series he is in, he is mostly a supportive character, not doing much outside of enoucragement and being there for the other heroes.
LuigiLuigi09876 makes his debut in this movie. He plays a very little role, but is very shocked with the Star World. He mainly helps MM.
He becomes slightly more active here, helping out the heroes and fans in getting the objects they need.
He becomes more of a main protagonist here, appearing in main protagonist groups and helping to get medals and be encouraging.
LuigiLuigi does fight at some points in this movie, and has a minorly active role, but doesn't do much outside of help and a few fights.
He's one of the main protagonists who helps alot during the movie. However, LuigiLuigi didn't collect a D-Star, and merely helped for encouragement.
In this movie, as a main protagonist, he gets possessed by Seziore, who is freed by MarioMario54321. Depending on the watcher's actions, if MarioMario54321 is possessed by Invort, LuigiLuigi09876 will save him as a return for MarioMario saving him.
He is one of the main protagonists in the movie. He has a particular dislike for anyone who breaks the fourth wall here, even going as far to minorly insult one of his friends. He does agree to the mission at hand though and still appears to be mainly supportive here.
He got himself trapped at Wet-Dry World and was freed by MarioMario54321. He seemed to be very confused as to what was going on, before getting an explanation by MM54321 himself.
- LuigiLuigi09876 is made up, and doesn't actually exist, except in MM54321's fanon.
Fourth Dimensional counterpart: FourigiFourigi09876
Star World counterpart: StarigiStarigi09876
Dimension X counterpart (doppelganger): Frozin (IgiulIgiul09876)