Dark Star Cluster

The Dark Star Cluster (暗黒星団) is a intergalactic crime network formed by four evil aliens.

History
They were first seen performing a robbery in a warehouse on Earth. When Alien Valky Halky's Samekujira Jolly came to Earth for its master, the team approached Xio and Jolly's owner, demanding it until Halky challenged them for a rugby match.