League of Villains

The Villain Alliance is a group of organized villains that is made up of weak and powerful villains. The leader of the alliance is Tomura Shigaraki while Black Mist acts as the second in command of the alliance. The mission of the Villain Alliance is to murder All Might.

History
The size of the Villain Alliance is estimated to be 75 (however, after the events at the USJ, the size of the alliance is dramatically decreased due to the majority of the villains belonging to the alliance along with Noumu being captured and detained by the Police).

The Villain Alliance attacked the USJ in an attempt to kill All Might. However, the majority of the Villain Alliance (except for Tomura, Black Mist and Noumu) are defeated by Class 1-A. After All Might arrives, Noumu engages All Might in battle and is defeated.Tomura and Black Mist try to finish what Noumu started but their attempt is thwarted by Izuku Midoriya and the timely arrival of the Yuuei Pro Heroes. Both Tomura and Black Mist are sucked into a Black Hole created by No. 13 (However, Black Mist creates a portal back to their hideout, teleporting themselves out of harm's way). Thus, the Villain Alliance is defeated and the majority of the villains of the alliance (along with Noumu) are captured and detained by the police, leaving Tomura and Black Mist as the only remnants of the Villain Alliance.

During the Yuuei Sports Festival, Black Mist sought out the Hero Killer, Stain, due to his notoriety. Black Mist manages to find Stain and asks for a moment of his time, teleporting himself and Stain away.