Said to be one of the oldest Lumas in existence, Polari serves as Rosalina's most trusted advisor. Having extensive knowledge of the Comet Observatory, Polari serves as a guide of sorts to Mario, showing him a map of all of the galaxies visible from that location, as well as all of the Prankster Comets on that Galaxy, if any. He will show off the map behind him when Mario needs to see what galaxies there are. It is unknown what happens to Polari at the end of the game; he is not seen flying into the giant black hole, and in the secret ending, he does not appear alongside Rosalina or in the Comet Observatory.
Polari shows certain similarities to Toadsworth. He is highly protective of the person he advises, and is additionally shown to have wisdom that proves useful to Mario on his adventure.
- Polari also appears in Super Smash Bros. for 3DS/Wii U as a Luma for Rosalina.
- The Prima guide treats Polari in the domes as separate individuals referring to them simply as Black Lumas.
- Unlike the squeaks the other Lumas give out when they talk, Polari himself talks in a less high pitched and muffled voice.