Isle of Ancients

The Isle of Ancients is a place in the Subspace Emissary, in Super Smash Bros. Brawl. Although never appearing in the game itself, it plays a great role in the Emissary.

When Tabuu first found the Isle of Ancients, he decided to use the robots, the residents, to help him make Subspace Bombs. So, he took the isle over, and used their advanced technology to build the subspace weapons, such as the aforementioned Subspace Bombs, and the Dark Cannons.

Later, however, Ganondorf takes control of the robots and forces them to blow up the Isle of the Ancients so that he can tear a hole in space large enough to fit a Subspace Gunship through.

Once the mass production of Subspace Gunships yielded a certain number of units, it would then be possible to launch all of them through the hole at once. Once the gunships were in our world, there would be no way to stop them from dragging all the remaining pieces of our world into theirs. Once that happened, there would be no more need for the Isle of Ancients or the Subspace Bombs.

The Destruction
Ganondorf took control of the robots and forced them to blow up the Isle of the Ancients so that he can tear a hole in space large enough to fit a Subspace Gunship through.

Once the mass production of Subspace Gunships yielded a certain number of units, it would then be possible to launch all of them through the hole at once. Once the gunships were in our world, there would be no way to stop them from dragging all the remaining pieces of our world into theirs. Once that happened, there would be no more need for the Isle of Ancients or the Subspace Bombs.

In the ending (or new beginning) of the game, the spot marked by the shining "X" is where the Isle of Ancients was. When Tabuu and the Great Maze were destroyed, most parts of the World of Trophies returned to normal, but the effect of so many Subspace Bombs going off at once made it impossible for the Isle of Ancients to return to normal.

Trivia

 * The Isle of Ancients resembles Angel Island from the Sonic the Hedgehog series, as they both have ruins of an ancient civilization and both float above the sea.