Traditional and terrifying masks of war were donned by the Kaleesh warlord Qymaen jai Sheelal, who later became known as General Grievous. One such mask was crafted using the skull and bones of the Mumuu, one of the most dangerous predatory animals found on Kalee, while another was fashioned from the bones of an Erkush. Before going into battle, the mask would be covered in Karabbac-blood war paint around the eye openings.
Bone was the material from which Grievous's Kaleesh masks were made. One of the terrifying and traditional war masks that Grievous wore was made from the skull and bones of the mumuu, one of Kalee's most deadly and fearsome predatory species. Another of his original masks was hewn from Erkush bone. The masks' teeth bore a resemblance to those of the karabbac. Before combat, the mask was painted with karabbac-blood war paint above Grievous's narrow, golden eyes.
The warlord Qymaen jai Sheelal, who would later become known as Grievous, wore a Kaleesh mask into battle for many decades before the Clone Wars. He wore it during conflicts like the Kaleesh-Yam'rii War between his people and the Yam'rii, until a sabotage shuttle crash left him critically injured, destroying the majority of his original body. When Grievous rose to the rank of General in the Confederacy of Independent Systems, he honored his home planet's customs by modeling his faceplate after the skull-like mask he had once worn as a feared warrior and warlord.
An Ithorian collector by the name of Dok-Ondar eventually acquired one of the original Kaleesh masks worn by the late General Grievous and put it on display at his Batuuan shop, Dok-Ondar's Den of Antiquities, which was located in Black Spire Outpost on Batuu. Vi Moradi, a Resistance spy who was hiding from First Order stormtroopers on Batuu, visited Dok-Ondar's shop some years later and noticed a mask that looked promising, but she quickly realized it was a Kaleesh mask, which would only attract unwanted attention.
The Dok-Ondar's Den of Antiquities store at the Star Wars: Galaxy's Edge theme park, which debuted at Disneyland Park and Disney's Hollywood Studios in 2019, was the first place Grievous's mask appeared. Although the owner of the mask was not identified until Cole Horton's 2020 reference book, Star Wars: Galaxy's Edge: Traveler's Guide to Batuu, it was confirmed to be Grievous's.
Grievous's masks were first introduced in the Star Wars Legends timeline in "The Eyes of Revolution," a comic book written and illustrated by Warren Fu that appeared in the Dark Horse Comics anthology Star Wars: Visionaries, which was released on April 2, 2005. They were also mentioned in "Unknown Soldier: The Story of General Grievous," an article by Abel G. Peña that was published in the eighty-sixth issue of Star Wars Insider on February 13, 2006.