Doctor Mikhail Sergeyevich Cossack appears in Archie Comics' Mega Man comic series in the fourth story arc/graphic novel, Spiritus Ex Machina. According to this continuity, he had traveled to America as a college student while undergoing his thesis in robotics research, and was likewise an old friend and colleague of both Dr. Thomas Light and Dr. Noele Lalinde because of this. He also made the acquaintance of Dr. Albert Wily, whom he evidently mistrusted very early on. Cossack's work in robotics was apparently esteemed enough that he started receiving funding for his research.
He met with Rock (Mega Man) and Roll at the Advanced Robotics Trade Show exhibition, quelling Pharaoh Man-the first of his Robot Masters to be constructed-for confronting Rock regarding Roll accidentally bumping into his daughter Kalinka, as he knew Dr. Light, when creating the two, would never intend for them to cause any deliberate harm. He then headed to the debate between Light and Lalinde regarding whether robots should possess advanced AIs.
After the Emerald Spears terrorist organization takes over the convention, Cossack proceeded, alongside Light and Lalinda, to debate with the ringleader, Harvey Greenleaf, about why they should or shouldn't destroy robots to distract him while Mega Man, Pharaoh Man, Quake Woman, and Elec Man locate the bombs wired in the building, and also told Kalinka, who called him out of worry for him, to stay with Roll in hiding. After Xander Payne took over the Emerald Spears, he questioned whether the robots personalities were indeed less real than those of a human. The doctors were later trapped underneath rubble when Xander detonated the last remaining bomb inside the lecture hall, although they were saved by Mega Man, Pharaoh Man, and Quake Woman. Cossack suffered a broken leg as a result of the cave in.
Dr. Cossack was later mentioned by Kalinka in issue 19, and makes a brief appearance in the Cossack Catcher in issue 20 while Mega Man was stuck in a time travel loop, where Cossack tells Mega Man he has no choice but to fight him, and also blames Mega Man for a girl's (implied to be Kalinka) incoming death, appears in one panel from issue 21 celebrating New Years with Kalinka, and watches his robots-Pharaoh Man and the newly built Bright Man-being disabled by Ra Moon's EMP in issue 28. After the EMP wave was dispelled and Ra Moon destroyed, Dr. Cossack, alongside Drs. Light and Astil, Pharaoh Man, Plant Man, Rush, and Roll accompanied Mega Man to Lanfront Ruins. He also made clear that he did not trust Wily and believed him to be lying, even getting into a brief argument with Dr. Light about the latter believing his claim of being one of Ra Moon's victims. However, he decided to put off the argument so they could at least discover the truth and prevent the blackout from ever occurring again, citing that his daughter is still having terrible nightmares of the episode.
Despite the evidence supporting Wily's claims, Mikhail remained skeptical, and in the end expressed a hope that Dr. Light would be as quick to defend his friends as his enemies. During the trip he also revealed his intent to start work on a digging Robot Master similar to Dr. Lalinde's "daughter", Quake Woman. In Issue 37, he alongside Wily and Light aided the Robot Masters in trying to track down the third generation of Robot Masters after they stole the Energy Elements, although he was still very suspicious of Wily. In a foreshadowing of things to come, his mug's handle broke off when Wily asked about how Kalinka is doing. He later reacted with horror upon learning that Wily had equipped his Wily Walker machine with chemical weapons. After the Wily Walker was "accidentally" activated by Dr. Wily, Cossack and the others tried to aid Mega Man, and got into an argument with Dr. Wily about the ethics of weaponizing Robot Masters (specifically Bright Man), although he relented at Dr. Light's suggestion. He reluctantly allowing Dr. Wily via Mega Man to modify Bright Man's light source, and also repaired a damaged Pharaoh Man in the aftermath.
Following Wily's apparent death in Issue 48, Cossack appeared in Issue 53, where he announced his intent to conquer the world with his eight Robot Masters and prove himself a superior robotics genius to Dr. Light. However, Dr. Light knew his friend well enough that Cossack would never jeopardize his work or Kalinka with such actions, and the wording of Cossack's speech also left Light suspicious that something was wrong with his friend. As Light suspected, Cossack's uncharacteristic actions were the result of Dr. Wily having his daughter Kalinka abducted via Break Man (the latter of whom was forced to do the deed under the threat of having his supposedly unstable nuclear core explode while among a civilian populace should he disobey his command) and forcing him to do what Wily wanted to ensure her safety. Prior to this, Dr. Light experienced a vision in which he witnessed Mega Man locked in battle with Cossack's Robot Masters as well as Mikhail piloting a curious machine.