Avengers: Infinity War will introduce Thanos' elite soldiers, the Black Order, but some newly surfaced promo art teases a mysterious new villain.

A new mug depicts some of the villains of the upcoming film, with the Infinity Gauntlet on one side, and Black Order members Corvus Glaive and Proxima Midnight on the other. The mystery, though, surrounds the figure pictured below them.

Theories range from a redesigned Black Dwarf (renamed Cull Obsidian in the film) to a leader of Thanos' genetically engineered Outriders, the aliens who make up the army that fights against Wakanda in the Infinity War trailer. Whoever, or whatever, it is, it's likely not a major player in the film, considering there are already so many characters in play.

RELATED: Is Avengers: Infinity War’s Mystery Villain An Outrider… Or Something Else?

Directed by Joe and Anthony Russo, Marvel’s Avengers: Infinity War stars Robert Downey Jr., Josh Brolin, Mark Ruffalo, Tom Hiddleston, Chris Evans, Chris Hemsworth, Jeremy Renner, Chris Pratt, Elizabeth Olsen, Sebastian Stan, Benedict Cumberbatch, Paul Bettany, Samuel L. Jackson, Cobie Smulders, Benedict Wong, Zoe Saldana, Karen Gillan, Vin Diesel, Dave Bautista, Pom Klementieff, Scarlett Johansson, Tom Holland and Anthony Mackie. The film opens May 4.

(via We Got This Covered)