|Portrayed by||Mo McRae|
- "Ty...Ty...Ty... Tyler."
- ―Tyler introduces to August Marks
Tyler Yost is the current leader of the One-Niners. After the death of Laroy Wayne, leadership passed to Darnell but he was set up by August Marks on behalf of Damon Pope, to help quell the tension left after Laroy's rampage following Veronica Pope's murder. When Darnell was then killed by Marks, he was chosen to lead the One-Niners, an assignment he nervously accepted.
Tyler was appointed leader of the One-Niners by August after watching the death of Darnell. Although unwilling at first, Tyler proves himself to be a capable leader who keeps his men in line. He also is quickly able to form a good relationship with Jax Teller, and is able to keep the peace in Oakland with the Mayans and the Lin Triad.
Tyler and the One-Niners are fully on SAMCRO's side during the sixth season. They help SAMCRO take out Bohai Lin and numerous Lin Triad members, saving Happy Lowman and proving August Marks as a worthy arms dealer to Connor Malone.
Tyler is instrumental in SAMCRO's opposition to both August Marks and the Chinese. He, along with the One-Niners, help SAMCRO take down the Lin Triad in return for SAMCRO's help dealing with Dulain and his rebel Niners crew. He proves to be a valuable "inside man" in August Mark's gang, providing SAMCRO with information about Marks while not giving away to Marks his allegiance to SAMCRO. His most important role is when he kills one of Mark's men and frees T.O. Cross and Ratboy Skogstrom from Moses Cartwright's torture room. He proudly tells Jax, "I did it" when he, Rat and T.O. arrive at the Aryan's farm where Moses and the rest of Marks' hit squad had just been massacred, the whole plan being pre-conceived and successful. Tyler's last role in the series is when he helps SAMCRO locate Connor Malone.
Tyler is a young African-American male in his late 20's to early 30's. When he originally appears, he is shown sporting longer curly hair with a mustache and goatee. In his later appearances, he has cut his hair down to a buzz and grown further fuzz along his jawline.
In all of his appearances, he is shown to have a diamond-studded earring in each ear. His attire consists of purple-themed shirts, often combined with a mixture of white to represent his colors for the One-Niners.
Despite being the leader of the One-Niners, he has shown to be a nervous and quiet leader. In comparison to the former leader Laroy Wayne who kept a calm collective especially around Marcus Alvarez and Henry Lin, Tyler stays back during meetings and only speaks when addressed. However, unlike the temporary leader before him (Darnell), he took up the position and has so far been successful in being allied with the other groups including SAMCRO.
He appears to be on a friendly basis with SAMCRO President Jackson 'Jax' Teller, as Jax stood in to speak on Tyler's behalf during a meeting with the Mayans and Triads. However, Tyler was one of a few individuals who witnessed the ruthlessness that Jax is capable of displaying when he found and murdered a man atop a roof, throwing his body over as it hit the street landing just a few yards from Tyler and his men.
- Unnamed Marks employee - Shot in the head. ("Faith and Despondency")
|Season 5 appearances|
|"Sovereign"||"Authority Vested"||"Laying Pipe"||"Stolen Huffy"||"Orca Shrugged"|
|"Small World"||"Toad's Wild Ride"||"Ablation"||"Andare Pescare"||"Crucifixed"|
|"To Thine Own Self"||"Darthy"||"J'ai Obtenu Cette"|
|Season 6 appearances|
|"Straw"||"One One Six"||"Poenitentia"||"Wolfsangel"||"The Mad King"|
|"Salvage"||"Sweet and Vaded"||"Los Fantasmas"||"John 8:32"||"Huang Wu"|
|"Aon Rud Persanta"||"You Are My Sunshine"||"A Mother's Work"|
|Season 7 appearances|
|"Black Widower"||"Toil and Till"||"Playing with Monsters"||"Poor Little Lambs"||"Some Strange Eruption"|
|"Smoke 'em if You Got 'em"||"Greensleeves"||"The Separation of Crows"||"What a Piece of Work is Man"||"Faith and Despondency"|
|"Suits of Woe"||"Red Rose"||"Papa's Goods"|