M'Baku was the leader of the isolated Wakandan tribe, the Jabari, which had retreated to the mountains of the country and renounced the use of Vibranium. During T'Challa's coronation ceremony at the Warrior Falls, M'Baku stepped forward to claim his right to challenge the would-be king for the throne, since he rejected the nation's modern lifestyle. Even though M'Baku temporarily overpowered his foe, T'Challa gained the upper hand. After pushing M'Baku to the edge of the cliff and pinning him, T'Challa forced him to surrender, since the only other alternative to end the fight would've been his death. After yielding, M'Baku was assisted in leaving Warrior Falls.
Not long afterwards, T'Challa confronted his cousin N'Jadaka in a combat for the throne at Warrior Falls, and was left for dead after being thrown off the cliff. His injured body was found by Jabari fishermen and was taken to M'Baku. As a repayment for sparing his life during their combat, M'Baku ordered T'Challa to be covered in snow in order to stabilize his failing vital signs. However, since the Jabari lacked the technological advancements of the rest of the country, they couldn't nurse him back to health.
M'Baku was subsequently approached by a group of subversive Wakandans, including Shuri and Ramonda, T'Challa's sister and mother, respectively. They rejected N'Jadaka as the king, and they sought M'Baku's help to overthrow him. After they offered him the last of the Heart-Shaped Herb, M'Baku decided instead to show them the injured T'Challa. Using the Heart-Shaped Herb, they managed to heal him. Once he was recovered, T'Challa thanked M'Baku for saving his life, and requested the assistance of the Jabari in opposing N'Jadaka. M'Baku refused to help T'Challa any further.
However, during the confrontation between T'Challa's supporters and N'Jadaka's forces, M'Baku and the Jabari Tribe appeared just in time and turned the tide of the battle. M'Baku's invaluable help in this battle gained his people a seat on the Tribal Council following T'Challa's return to the throne.
M'Baku helped fight in the battle against the Black Order alongside the Avengers and the tribes of Wakanda. Their combined efforts proved to be nothing against the Mad Titan, Thanos. When Thanos snapped his fingers, as half of the universe turned to dust, M'Baku stared in horror as his people were dying before him.
5 years after the Blip on Earth, Bruce Banner was able to bring back the half of the universe that had been snapped away and M'Baku helped the rest of the forces of the galaxy in the Battle for Earth against Thanos and the Black Order. 
- Winston Duke portrays M'Baku in the films Black Panther, Avengers: Infinity War, and Avengers: Endgame. Duke will reprise his role in the upcoming film Black Panther: Wakanda Forever.
- Winston Duke's popular portrayal of the character has led to fans taking to social media to enact the "M'Baku Challenge," in which fans (mainly through Snapchat) re-enact M'Baku's entrance in the Challenge Day scene.
- 3 appearance(s) of M'Baku (Earth-199999)
- 1 mention(s) of M'Baku (Earth-199999)
- 6 image(s) of M'Baku (Earth-199999)