Streets of Rage/Bare Knuckle Final Boss: Mr. X

Mr. X (Streets of Rage), Videogaming Wiki

Streets of Rage Mr. X by TenderSman on DeviantArt

Sigma Posting on X: Mr. Σ Source: Mr. X Streets of Rage 2 (Genesis) by Sega, Ancient, MNM Software, Shout! Designworks and H.I.C. / X

Mr X (Character) - Giant Bomb

Streets of Rage 4

Streets of Rage - Final Showdown (Big Boss/Mr. X Remix)

Shiva joins the playable roster of Streets of Rage 4: Mr X. Nightmare – Destructoid

Streets of Rage 2 Mr X Greeting Card for Sale by retrogameprints

Streets of Rage 2 Mr X Kids T-Shirt for Sale by retrogameprints

Streets of Rage 4 Mr. X Nightmare DLC adds three new playable characters