Shadow Bugs are purple-black orbs appearing in Super Smash Bros. Brawl that can form Primids and other kinds of enemies. All of the Shadow Bugs are stored in the Halberd which commonly drop Shadow Bugs throughout episodes. They also have the ability to copy a character when in trophy form into a purple tinted evil one which also possesses dark purple aura around it and yellow pupils. They can also be altered in size as the evil Diddy Kong clone turned bigger.
Embodiments of a primordial substance that can take the form of any number of lesser Subspace foes. They can also copy the forms of trophies to create evil doppelganger versions of them. The mysterious substance inside Mr. Game & Watch can be extracted endlessly. Once Tabuu discovered this, he used Mr. Game & Watch to create the Subspace Army.