Markus "Mark" Sebastian Grayson, also known as Sinister Invincible, is a major antagonist in the Invincible franchise. He was among the 20 villainous Invincibles recruited by Angstrom Levy to ruin his home dimension's Invincible's reputation after he disfigured him horrendously and killed all of his counterparts under the promise of granting every Invincible access to new dimensions to conquer. Levy would prove to not respect the deal, as he betrayed the 8 surviving Invincibles as soon as he got the chance by stranding them in a wasteland version of Earth. During this time, this particularly Sinister version of Invincible would resort to anything that would ensure his survival, including cannibalizing his other selves, making him one of the far more malicious versions of Invincible. Sinister closely resembles his main timeline counterpart, sporting black hair with a distinctive widow’s peak combed back, accented by a few stray strands. He has a lean, well-defined physique. The primary difference is his noticeably paler complexion compared to the main Invincible. During Sinister and the variants in time in the Wasteland Universe, he would grew half of his hair and a beard. Attire Sinister’s costume closely resembles that of his mainstream counterpart but features a striking black and yellow color scheme. His outfit includes a large yellow cape, full-fingered yellow gloves (in contrast to the original’s fingerless ones), and black visors integrated into his mask. Notably, his costume lacks knee pads, and the bottom of the “i” emblem on his chest is flat rather than pointed. Additionally, his mask fully encircles his eyes, unlike the main Invincible’s design. During his last appearance in the Wasteland Universe, most of his outfit was all torn apart and one of his goggles was broken. Little is known about Sinister's past, but it's implied that most of his life had been similar to the mainstream Invincible's, with the exception that something had made him closer to his father, leading him to a darker path that culminated in him joining the ranks of the Viltrum Empire. According to him, his world's version of Firebreather is the king of all monsters and one of the most ferocious villains he had ever faced during his time as a superhero, which could lead to the hypothesis that everyone is a little more "evil" in Sinister's dimension. It's also mentioned by Mask Invincible that, sometime after becoming a villain, Sinister had murdered his own mother, Debbie, in their own home, which made him hate coming back to that place. extreme psychopathy, sadism, and a total lack of empathy.