Avengers: Endgame concept artist Jerad S. Marantz offered a horrifying up-close look at one of Thanos' Chitauri gorillas without a mask.

"Here’s a look under the helmet of my Chitauri gorilla form the final battle in Avengers: Endgame," Marantz said on his Instagram post. "It still amazes me, the timeline from when I completed this design to it showing up in the film. As I mentioned before, this was a last minute design and once it was approved it showed up in the film in a matter of weeks."

RELATED: Avengers: Endgame Concept Art Shows Thanos at Peace

Avengers: Endgame showed the Chitauri gorillas fighting alongside Thanos against the Avengers in the movie's final battle sequence. In the film, the creatures are shown wearing masks, which Marantz mentioned was a good decision.

Disney's Avengers: Endgame took place in the aftermath of Thanos' snap and showed Earth's Mightiest Heroes traveling through time and space to bring back their loved ones and everyone else lost. Endgame has been widely-successful and became the highest-grossing film of all time. The film has currently made $2,797,800,564 at the box office, worldwide.

Jerad S. Marantz has served as the concept artist on many Marvel Cinematic Universe films, including Avengers: Infinity WarSpider-Man: Far From Home and Guardians of the Galaxy Vol. 1 and Vol. 2. 

RELATED: Avengers: Endgame Concept Art Puts War Machine in Outer Space Armor

Directed by Joe and Anthony Russo, Avengers: Endgame stars Robert Downey Jr. as Iron Man, Chris Evans as Captain America, Mark Ruffalo as Bruce Banner, Chris Hemsworth as Thor, Scarlett Johansson as Black Widow, Jeremy Renner as Hawkeye, Brie Larson as Captain Marvel, Paul Rudd as Ant-Man, Don Cheadle as War Machine, Karen Gillan as Nebula, Danai Gurira as Okoye and Bradley Cooper as Rocket, with Gwyneth Paltrow Pepper Potts, Jon Favreau as Happy Hogan, Benedict Wong as Wong, Tessa Thompson as Valkyrie and Josh Brolin as Thanos. The film is now available on Digital HD, Blu-ray and 4K UHD.