Luma

Lumas are star-like creatures that first appear in Super Mario Galaxy. Unlike most Stars, they have a tear drop-like shape, and come in many colors. They are much like Power Stars, but are more circular and have the ability to talk. Lumas boast the ability to transform, from minor planetoids to entire galaxies, and according to Rosalina, some Lumas can even transform into Power Stars. They call Rosalina their "mama", and most of them make their home with her in the Comet Observatory, although others live on Starship Mario following their leader Lubba. Their name comes form the Latin word for light, lumen, which is a reference to their future as stars. In Super Mario Galaxy 2, if the Co-Star Luma spins one, it will emit three Star Bits.

Paper Mario featured a similar species, called Star Kids. Like the Lumas, the Star Kids were young stars, who were raised on a special place to become real stars someday. They also possessed magical abilities, like the Lumas, and a very similar, childish behavior. In addition, Blue Lumas look similar to an item in Paper Mario: The Thousand-Year Door called Mini Mr. Mini.

Super Mario Galaxy
In Super Mario Galaxy, various Lumas appear on the Comet Observatory and in different galaxies, and Mario is accompanied by a uniquely cream-colored Luma, who was given to him by Rosalina at the beginning of the game. Luma grants Mario the power to do spins. While he is the only cream-coloured Luma encountered by Mario, the Luma that transformed into the comet that Rosalina and the Lumas travel is shown to be the same colour in Rosalina's storybook's illustration.

Yellow Lumas transform into Sling Stars and Launch Stars (and possibly Power Stars) and are the most common variety. Red Lumas guard Red Stars. Green Lumas are the guardians of the Trial Galaxies and transform into green Launch Stars and Green Stars. Blue Lumas transform into Pull Stars. Pink Lumas transform into pink Launch Stars to get to hungry Luma galaxies. Lumalee, who is a large, light-blue Luma, hosts the Luma Shop. There is also another type of Luma that is pink, known as the Hungry Luma. The last type of Luma is the Lumacomète, which has the ability to move Prankster Comets.

In the end, all the Lumas (including Mario's Luma) throw themselves into the massive black hole created by Bowser's dying sun to neutralize it. However, Luma is reborn and living on a small planet while it is hinted that the other Lumas will be reborn later. Indeed, they appear in the sequel.

Super Mario Galaxy 2
Lumas also appear in Super Mario Galaxy 2. Some time before the beginning of the game, Bowser attacked Lubba's ship, and many of the Lumas on board fell down to the Mushroom World. A large number of Lumas are shown to reside in Starship Mario, and their leader is Lubba. Hungry Lumas also appear; this time, they ask to be fed both Star Bits and Coins. Like in the last game, Lumas enjoy being fed Star Bits, and may thank the player if he or she decides to shoot star bits at them. There are exceptionally large species of Luma in the Supermassive Galaxy, called Giant Lumas. Additionally, Mario's companion Luma returns in this game; however, Mario doesn't seem to remember him, and he found the baby Luma when he crashed onto the Mushroom World.

Mario Kart Wii
In Mario Kart Wii, a Yellow Luma revolves Rosalina at all times. It makes tiny noises whenever Rosalina does a trick in the air. It has no effect on gameplay. For players that unlock Rosalina without a save data of Super Mario Galaxy, the Luma revolving around her will have straight edges instead of having a tear-dropped shape body.

Mario & Sonic at the London 2012 Olympic Games
Yellow Lumas appear in Mario & Sonic at the London 2012 Olympic Games in the Dream Spacewalk event. Here, they aid the athletes in defeating Dino Piranha. They first transform into Launch Stars that send the characters into space. Following this, they periodically appear to create rings that the athletes must all pass through in order to damage Dino Piranha.

Fortune Street
In Fortune Street, Lumas appear in the unlockable Good Egg Galaxy board.

Mario Tennis Open
A Luma is a playable character in Mario Tennis Open. It is a Technique-type player and it can be unlocked by completing level 3 of the Galaxy Rally special game. Its racquet is turquoise with a picture of a Luma on it. Red, Green, and Turquoise Lumas appear in the background of the Galaxy Arena court. Also if the player is playing as Luma while playing the Galaxy Rally game, the opponent Luma will be blue.

Color Variations
Lumas come in a variety of different colors, some of which have abilities to help Mario/Luigi on his adventure.

Mario Tennis Open
Character Type: Technique

Site Bio: ''Luma joins Mario Tennis for the first time! Luma floats through the air, aiming shots toward the far corners of the court.''

Bio 2: ''Luma has come down from the night sky to make his Mario Tennis debut! Though he may look gentle and fluffy, his clinical shots head straight for the corners of the court!''

Trivia

 * Excluding the 3DS version of Mario & Sonic at the London 2012 Olympic Games, Mario Tennis Open is the only game where Lumas appear in a 3DS game.