Warning: SPOILERS for Invincible, and for the storyline of Mahershala Ali's character, Titan, as well as general spoilers for both seasons of Luke Cage.
Mahershala Ali's role in Invincible mirrors his memorable turn as the villain Cottonmouth in Luke Cage. Amazon Prime Video's adaptation of Robert Kirkman's beloved superhero comic boasts an incredible cast to play the vast amount of characters it includes. Mahershala Ali is one of many talented actors to voice Invincible's characters, and he was momentarily featured in the very first episode. His character, Titan, is the first bad guy Invincible stops after gaining his superpowers.
Following this brief introduction to Ali's character, Invincible episode 5 gave the two-time Academy Award winner a bigger role to play. Titan has a central role in the episode as he recruits Invincible to help him take down the crime boss Machine Head. Titan and Invincible attempt to surprise attack the villain, but he knew they were coming and was prepared. The duo fought various combatants but they are quite easily overpowered. Machine Head was still defeated thanks to the Guardians of the Globe, which allowed Titan to climb the criminal food chain as he always planned.
Now that Titan is at the top of a criminal empire, Ali providing the voice for the character immediately brings to mind his role as Cottonmouth. Ali played Cornell "Cottonmouth" Stokes for the first half of Luke Cage season 1. Cottonmouth led one of Harlem's most powerful criminal empires. On a basic level, this provides commonality between Ali's two roles, as Cottonmouth and Titan are scheming crime bosses. Stokes rose to power after a rough upbringing and loved the glamor that came with his wealth and power. This is similar to Titan's arc in Invincible. His play to take Machine Head's place was done to make a better life for his family, and eventually others, and he so far embraces benefits that come with the position.
Titan and Cottonmouth might both be crime bosses, but Ali's two roles are quite different beyond that. One of the biggest differences between them is that Titan has superpowers. He has superstrength and the ability to form rocks around his body, which makes him nearly bulletproof. This essentially makes him a mix of Cottonmouth and Luke Cage, or even the crime boss version of Luke featured at the end of Luke Cage season 2.
The good news for Invincible and Ali fans is that Titan should continue to be part of the show's story and future. As Luke Cage viewers surely remember, Cottonmouth's death at the end of episode 7 came as a massive surprise. Invincible is only beginning to explore Titan's story and episode 5's ending sets up where it is heading next. With the series still needing to tackle Titan's involvement with The Order and more, Ali's voice will continue to be heard in Invincible.