Prankster Comet

"It seems that a Prankster Comet has appeared somewhere...Prankster Comets have very strange effects on galaxies..."

- Rosalina

Prankster Comets are comets that appear in Super Mario Galaxy and Super Mario Galaxy 2. They will appear from time to time in the orbits of the fifteen main galaxies, starting at the point when Mario or Luigi collect their thirteenth Power Star.

If the player travels to a galaxy when a Prankster Comet is in orbit, a special event will be triggered, which will usually change the gameplay of the level. Prankster Comets will only appear in galaxies after a specific Power Star in any given galaxy is collected. Also, when a Prankster Comet is in orbit, the player is forced to choose its level. No option is given to choose "normal" levels. However, the Prankster Comet Luma positioned near the Terrace will shuffle the comets between available galaxies if fed twenty Star Bits by the player.

By completing the event, the player will receive a Power Star. While a Prankster Comet is in orbit of a galaxy, players will need to completely restart the level each time they lose a life, instead of coming back at the last check point. Once a Prankster Comet's star has been collected, its star will become a selectable mission, only causing the comet to return to the corresponding galaxy at the player's request. All of the Prankster Comets (except some Purple Comets) also have their own music that plays during their missions.

In Super Mario Galaxy 2, Prankster Comets only appear once the player has collected a Comet Medal in a certain galaxy, and has collected a certain number of other comet medals from other galaxies. In this game Prankster Comets with different effects are no longer considered different types of Comet. Galaxies under the influence of a Prankster Comet are given a generic symbol. Below, the Super Mario Galaxy 2 comets are grouped together based on the title of the mission they appear in. Some comets are now yellow if they give Power Stars, while green if they give Green Power Stars. Traveling to a galaxy with a comet in orbit opens up the comet Star mission, although the player may have the option to select the mission, as opposed to the first game.

There are five different types of Prankster Comets in the first game, each one a different color: red, white, blue, yellow, or purple.

[[File:Smg icon speedycomet.png]] Speedy Comet
The Speedy Comet (レッドコメット Red Comet)  requires Mario to complete a level within a certain time limit, usually from 4 to 6 minutes. Also, there will be small changes in the galaxies. For example, Good Egg Galaxy's boulders are all replaced by Chomps. Four galaxies are visited by the Speedy Comet: the Good Egg Galaxy, Dusty Dune Galaxy, Space Junk Galaxy, and Dreadnought Galaxy. This comet also reappears in Super Mario Galaxy 2. A list of galaxies visited by it includes the Sky Station Galaxy, Bowser Jr.'s Fiery Flotilla, Hightail Falls Galaxy, Bowser's Lava Lair, Rolling Masterpiece Galaxy, Supermassive Galaxy, Bowser's Gravity Gauntlet, Throwback Galaxy, Bowser's Galaxy Generator, the Stone Cyclone Galaxy, and the Boss Blitz Galaxy.

Galaxies marked with * next to their time limits have Timers scattered throughout the mission; collecting one adds 10 seconds to the player's time limit. However if the player loses a life, then the Time will be set back to where it was at the point where the player lost the life.

[[File:Smg icon daredevilcomet.png]] Daredevil Comet
The Daredevil Comet (デスコメット Death Comet) sets Mario's max health to only one unit, as opposed to the usual three (or six with a Life Mushroom). Additionally, it removes all Life Shrooms and even coins from the level so that Mario cannot get them. Five galaxies are visited by the Daredevil Comet: the Battlerock Galaxy, Ghostly Galaxy, Gusty Garden Galaxy, Deep Dark Galaxy, and Melty Molten Galaxy. Four of them have the player fight a previously fought boss: Topmaniac, Bouldergeist, Major Burrows, and Kamella respectively, with the sole exception being Melty Molten Galaxy, which has the player complete the entire first mission (The Sinking Lava Spire) with only one health unit.

The Daredevil Comet is also in Super Mario Galaxy 2 in Spin-Dig Galaxy, Bowser Jr.'s Fearsome Fleet, the Slipsand Galaxy, Bowser Jr.'s Boom Bunker, the Battle Belt Galaxy, and the Grandmaster Galaxy. Unlike with the prequel, however, some of the Daredevil Runs in Super Mario Galaxy 2 have Checkpoint Flags.

[[File:Smg icon cosmiccomet.png]] Cosmic Comet
The Cosmic Comet (シャドウコメット Shadow Comet)  pits Mario in a race against Cosmic Mario in a predetermined course with a star at the end. Mario must beat his duplicate to the Star. Four galaxies are visited by the Cosmic Comet: the Honeyhive Galaxy, Freezeflame Galaxy, Gold Leaf Galaxy, and Sea Slide Galaxy. If the player is playing as Luigi, they will be racing against Cosmic Luigi instead. Unlike Cosmic Mario, Cosmic Luigi is more intelligent, and will take advantage of any shortcuts that are available.

[[File:Smg icon fastfoecomet.png]] Fast Foe Comet
The Fast-Foe Comet (クイックコメット Quick Comet) speeds up all enemies or objects in a stage. Mario must complete the stage while avoiding the accelerated enemies or objects. Only two galaxies are visited by the Fast-Foe Comet: the Beach Bowl Galaxy, and Toy Time Galaxy. Tox Boxes, Thwomps, and moving platforms are the only things affected.

[[File:Smg icon purplecomet.png]] Purple Comet
The Purple Comet (パープルコメット Purple Comet) is only available after the main story is beaten. Purple Coins are hidden throughout the galaxy, and Mario must retrieve one hundred, sometimes within a time limit, to retrieve the Star. Some Purple Comet missions have more than one hundred Coins, but Mario still only needs to collect one hundred for the Star. All fifteen "main" galaxies are visited by the Purple Comet. Timed Purple Comet missions, as well as the Battlerock and Dreadnought Galaxy's Purple Comet missions have unique background music, which includes a remix of the Gusty Garden Galaxy music.

There are also Purple Comets in Super Mario Galaxy 2. They are the same as Super Mario Galaxy but, instead of having to beat the game for Purple Comets to come, only the Galaxy's Comet Medal is required.

[[File:Smg2 icon prankstercomet.png]] Clone Comet
Multiple Cosmic Clones appears on a selected mission. The player needs to redo the whole or part of the mission while there are Cosmic Clones. The comet appears in the Cloudy Court Galaxy, the Haunty Halls Galaxy, the Chompworks Galaxy, and the Flip-Out Galaxy. It is fused with the missions Luigi's Purple Coin Chaos, Green Star 2 for Flip-Out Galaxy, and Puzzle Plank Galaxy's Purple Coin Shadow Vault.

[[File:Smg2 icon prankstercomet.png]] Romp Comet
Defeat a certain amount of enemies in a time limit, often with a power-up. The comet appears in the Yoshi Star Galaxy, the Boulder Bowl Galaxy, the Flash Black Galaxy, and the Shiverburn Galaxy.

[[File:Smg2 icon prankstercomet.png]] Double Time Comet
Makes the player redo a level, but with the objects moving faster. It appears in Beat Block Galaxy and Twisty Trials Galaxy. This is slightly similar to the Fast Foe Comet from the first game, except that stage hazards move faster instead of enemies, and the overall speed at which objects move is much greater than that of a Fast Foe Comet.

[[File:Smg2 icon greencomet.png]] Green Comet
Makes Green Power Stars appear in various levels in every galaxy except the Grandmaster Galaxy, usually in hidden or hard-to-reach places. For galaxies in which there are a total of six Power Stars, Green Power Stars will always appear in the last three levels of the galaxy. For galaxies that have only four Power Stars total, Green Power Stars will always appear in the last two levels of the galaxy. In either case, Green Power Star levels are always named as "Green Star 1" and "Green Star 2" (as well as "Green Star 3" for galaxies with six Power Stars total) as opposed to being named in the same way as normal galaxy levels.