The Mutai, also known as the "trial of blood," is an alien fighting tradition created by the Yolu as a means for settling disputes without resorting to war and has since been adopted by many other worlds to whom it is a greatly cherished tradition.
A Mutai is overseen by a Muta-Do, the "sayer," an elite veteran fighter who selects combatants, declares winners and presides over all matches. During matches two competitors—referred to as "Mutari"—are expected to continue to fight until one or the other can no longer fight or until the Mutai-Do declares the match a draw. There are no rounds or protective gear allowed other than a simple gi-like garment.
A Mutai was established on Babylon 5 in 2256 and before it's second year was up, five non-humans had been killed and many more crippled. In 2258 Walker Smith became the first Human allowed to compete. Though the Muta-Do initially rejected his clumsy, disrespectful attempt to join, he later challenged Gyor, the Babylon 5 Sho-rin. The fight ended in a draw and the Mutai-Do was impressed with Smith's performance and said that from then onwards, humans may enter the ring as brothers to all Mutari.
Mutari wear different colour sashes to denote rank and competence over a gi-like garment that also features the similarly symbol of the individual Mutari's world or race on the left breast. Lower ranking Mutari wear a yellow sash, higher ranking Mutari wear red and Mutai-Do wear a long robe with a purple coloured symbol. The Ka-Tow wear a training vest with a two pronged circular symbol on the left breast.
- Ka-Tow: A coach or "second" to a Mutari. A Mutari may have more than one Ka-Tow and they are sometimes former Mutari themselves.
- Mutari: The collective name for those that fight in the Mutari, who walk in the Sands of Blood.
- Mutai-Do: Leader of a local Mutai championship and match referee.
- Sho-rin: Champion of a local Mutai. Referred to as the master of the Mutai, bravest of the brave.