Fiery Dino Piranha is the third mission of the Melty Molten Galaxy in Super Mario Galaxy. The mission's objective is to defeat Fiery Dino Piranha.
The player starts on the starting planet once more and they have to go around the volcano similarly to how they did in the first mission, though there are more sinking platforms and they are smaller. At the end of the sinking platforms path is a segment where Mario has to jump up platforms and avoid lava plumes to reach a Warp Pipe that will take the player to the saucer of the Hardening Lava Planets. On the main planet, the player has to defeat all of the Li'l Cinders to make a Launch Star appear, that will send Mario to a similar planet, though this one is rotating and has many fireballs. The Launch Star on the other end will send Mario to a two-dimensional platforming segment where the player has to collect five Star Chips to form another Launch Star that will take the player to a group of sinking platforms. Using Sling Stars to cross the platforms, the player can reach a Launch Star that will take the player to the planet where Fiery Dino Piranha is fought.
Fiery Dino Piranha has the same tactics and is defeated similarly as Dino Piranha. However, unlike its standard counterpart, Fiery Dino Piranha is on fire and will burn Mario upon contact. As Fiery Dino Piranha moves around, it will leave behind a trail of fire. Initially, the player has to spin into Fiery Dino Piranha's tail to knock it into the eggshell, shattering it, though the player has to spin into the tail when it is extinguished. After the shell is shattered, Fiery Dino Piranha will begin chasing after Mario. When it is extinguished, Mario has to spin into Fiery Dino Piranha's tail to send it back at its head, damaging it. After damaging Fiery Dino Piranha three times, it will begin shooting out fireballs. The intervals at which its tail extinguishes and lights up also get shorter after each hit to the tail. Sending the tail back at it once more will defeat Fiery Dino Piranha and reward the player with a Power Star.