As the Elder of the Border Tribe, M'Kathu attended the ceremony during which T'Challa would be crowned the new King of Wakanda. Standing alongside the other members of his tribe, notably W'Kabi, M'Kathu announced to Zuri that the Border Tribe would not challenge T'Challa for the throne.
M'Kathu then watched the duel between T'Challa and M'Baku, the leader of the Jabari Tribe who had come to claim the throne. Like the rest of the Wakandans, M'Kathu strongly encouraged T'Challa and cheered upon his victory. Later, M'Kathu took part in a Tribal Council meeting in which Okoye announced that they had intel about Ulysses Klaue, with an opportunity to capture him.
As an unidentified individual arrived in Wakanda, claiming to have killed Ulysses Klaue, M'Kathu joined an emergency Tribal Council meeting summoned by T'Challa. Like the other Elders, M'Kathu was surprised to learn that the newcomer was actually N'Jadaka, also known as Erik Killmonger and the son of late Prince N'Jobu. When N'Jadaka claimed the throne of Wakanda, M'Kathu admitted that his demands were legitimate.
As a result, M'Kathu attended the duel between T'Challa and N'Jadaka. As T'Challa was defeated and thrown down the Warrior Falls, M'Kathu was forced to pledge fealty to N'Jadaka as the new King of Wakanda. M'Kathu then attended a Tribal Council meeting in which N'Jadaka announced his intent to send Vibranium-made weapons all over the world to trigger a global revolution spearheaded by Wakanda.
In the end, N'Jadaka was defeated by a returning T'Challa. Despite the Border Tribe fighting alongside N'Jadaka during the Battle of Mount Bashenga, M'Kathu retained his seat in T'Challa's Tribal Council.
- Kimoyo Beads: Like many other Wakandans, M'Kathu carried a wristband of Kimoyo Beads he could use for various purposes.