Darkroaches are Category Unknown Undead who are created in overwhelming numbers by the Stone of Sealing once the Giraffa Undead is sealed and Hajime Aikawa, the Undead known as Joker, is the victor of the Battle Fight. They serve Joker for purpose of destroying all life on the Earth prior to the Battle Fight resetting, targeting humans endlessly. When they die, they dissolve into green mist, only to be replaced with even more Darkroaches thanks to the Stone. Once Blade became the Navy Joker, the Darkroaches' existence was no longer needed.
Kamen Rider Decade
In the World of DiEnd, the Darkroaches are the minions of Fourteen, going after any one who breaks the law. Many of them are killed by the Riders and when their master is destroyed by Decade and Armed Hibiki, the remaining Darkroaches fade away into nothingness.
Other versions of the Darkroaches appear among the rankings of Dai-Shocker.