Melty Monster Galaxy
Melty Monster Galaxy is the first galaxy of World 6 in Super Mario Galaxy 2. The galaxy is completely covered in lava, with a magma tide that rises and falls every so often. The main obstacle here is the magma and its tide. As the name suggests, the most common enemies in the galaxy include giant lava monsters known as Magmaarghs and Magmaws. However, Octogoombas, Li'l Cinders, and Pinheads are also found.
NOTE: Unless otherwise noted, all names are unofficial.
Near the starting platform, there is a group of five small lava-covered planets that Mario cannot reach. Magmaarghs are the only creatures that inhabit these planets, lurking in the lava and attacking by surprising their prey. A set of Pull Stars are found among the Lava Planets in the first mission, The Magnificent Magma Sea. The player must carefully navigate the Pull Stars while avoiding the Magmaarghs to reach the Launch Star. The Launch Star takes Mario to another Launch Star which the player must quickly use to avoid a lunging Magmaargh.
Magma Sea Planet
This planet has many volcanoes on its surface, and there is a river of lava where Mario lands. Waves of lava can cover some low platforms, so the player needs to reach higher ground to be safe. Octoombas, a Li'l Cinder and a single Magmaargh roams this planet. Near the river, there are also tornadoes that Mario must use to make his way up a lava fall.
This isolated planet looks similar to the Lava Planets, but it has a small field of asteroids surrounding it. Mario can only access these asteroids. Even though they are very close to the surface of the planet, the gravity of the lava planet does not affect Mario, as he can run all around on the asteroids. The planet has several Magmaws moving around. Their mouths are open as they move, engulfing the asteroids temporarily and burning Mario. Another Magmaargh is found here hidden among the Magmaws. A Comet Medal is found on one of the asteroids, and a Crystal located on the planet contains the mission's Power Star.
This zone is a long path where the Rock Mushroom is used. This area has many platforms, some of which are separated by large voids. The Rolling Lane is an area that only Rock Mario can pass, as the zone has jump ramps that only Mario in his Boulder form can use to cross the gaps and reach the platforms. A few sections of the road are protected by rubber fences, and if Rock Mario rolls towards them, he will rebound back.
The Bowling Lane is a special area that Mario can only reach via the Warp Pipe found on the starting planet. This area is sort of similar to the Rolling Lane. Mario must use the Rock Mushroom to play a bowling game, earning points by smashing Pinheads, the only enemies found on the planet. The Chimp, who is in charge of the game, is found here. If Mario walks over the blue line, it will be a foul, and the Pinheads will disappear until Mario steps back again.
Green Star 1
This Green Star is located between two lava planets, above the Launch Star. Mario must quickly use the last two aligned Pull Stars once the Magmarrgh passes by, grabbing onto the last one. If the player lets go before Mario is in the center of the Pull Star, he will have enough speed to make it past the Launch Star and to the Green Star.
Green Star 2
This Green Star is located on the Magma Sea Planet. At the end of the tornado path, Mario must grab the vine, get maximum momentum, and jump to the Green Star. It is also possible, to get to the Green Star without the vine by using the last tornado but it is much harder that way.
Green Star 3
This Green Star is located on the Rolling Lane. The player must use Rock Mario until he reaches the last platform in the section shaped like an "N". The Green Star is not far off from the bottom right point, so the player must bounce Mario off of the top left point, and then aim towards the bottom right. If done correctly, Mario rolls right into the last Green Star. However, should the player miss, Mario is sent plummeting into space.
Alternatively, Mario can go to the end of the course, where the normal Power Star waits. Crashing into the lone block in the far left corner turns Mario back to normal, and he can then Long Jump back to the N-shaped platform by standing on the fence. This makes it much easier to collect the Green Star, either by precision jumping or by lining up the trajectory for his Rock form.
The background music for this galaxy is featured as a track in Super Smash Bros. Ultimate. It also has the slightly longer opening from the soundtrack version.
Prima Official Game Guide description
Names in other languages