Dark Star X

Dark Star X appeared in 2009 video game called Mario & Luigi: Bowser's Inside Story. Dark Star X is the sixth boss class located in the Gauntlet, which is inside the Challenge Node. It is the second-strongest boss in the game (after Bowser X). To start, 2500 coins must be paid to battle Dark Star X. It fights along with Dark Satellmite X's. The bros. have up to 12 turns to destroy Dark Star X. If the player defeats it, he or she will unlock Class 7, where they will fight all previous classes, including the Dark Star X, and Bowser X.

During the battle, Dark Star X is similar to the original Dark Star, only stronger and with the opposite color scheme. In the DS version, it is red with blue eyes, while in the 3DS remake, it is yellow with pink eyes.

Some changes are that the Dark Satellmites X's energy beams travel and Kamikaze attacks move faster, just as the Dark Star's clones do; there are also always seven clones (or nine, with sufficient damage) and they disappear earlier. When the bros' shadows come to life, they always split in two, something the original Star only did when it had been weakened.

If fought under the recommended level 40, the ramming attack after the laser and the ultimate vacuum will often defeat the bros instantly, even if they’re at full HP.