Some TMNT stuff was always meant for grownups.
Azokk believed that the conflict between the Triceratons and the Styracodons should have a peaceful solution, and traveled to the Styracodons to negotiate a treaty. However, he was betrayed and captured, his horns cut off and both his eyes gouged out, and was sent to a Styracodon extrajudicial prison to live out his days.
32 years later, Michelangelo was sent to the same prison, having been captured and smuggled off Earth after a one-night stand with the Styracodon Regenta Seri. Azokk had been in the prison long and had been resigned to his fate, but he soon shepherded and befriended Mikey to his new plight. Azokk finds it remarkable that Mikey continues to hold out hope even after his kidnapping, imprisonment and weeks of torture and starvation.
One day, in the prison courtyard, Mikey and Azokk are together in the courtyard. Mikey sees Seri being escorted by Styracodon bodyguards atop one of the high prison walls. Azokk listens as Mikey daringly scales the walls for a chance to see Seri again, but is overpowered by the guards and knocked back into the courtyard.
Later, back in their cell, Azokk makes a decision to try to free his hopeful young friend. Azokk strangles a fellow O'quaqui prisoner and capitates him with his jaws, recognizing that the enzymes in O'quaqui blood are a powerful acid that can dissolve through their prison shackles. Azokk and Mikey start making their escape, but Azokk's speech quickly becomes muddled as the acidic blood has started to dissolve his own mouth. Azokk admits that he knew the it would be fatal to him, but he sacrificed himself so Mikey could be free. Mikey can only watch in horror as his first real Triceraton friend succumbs and dies from the acid. Azokk's selfless death leaves a strong mark on Michelangelo's psyche.
As Mikey makes his way across the countryside of the Styracodon-controlled planet, he stumbles across a clandestine cell of Triceraton soldiers. They stun him and drag them into their facility. Mikey is initially horrified to wake up in a room full of Triceraton men, but they mean him now harm. Mikey explains his prison escape, but the Triceratons are alarmed to learn that Azokk was the name of the prison cellmate who sacrificed himself to save Mikey's life. The soldiers reveal they were a covert unit trying to rescue Azokk, but his death means they now have to withdraw. The Triceratons destroy their clandestine base and evacuate with Mikey off the planet back to Triceraton space.
Michelangelo is still suspected in Azokk's death, and is put on trial. He tells his story, and the court reveals they had been using a mind-reading device on him to confirm that he was telling the truth as he understood it. Now cleared of any wrong-doing in Azokk's death, Mikey is accepted as an honored guest of the Triceratons. But coupled with the details learnt from Mikey's testimony, Azokk's death as a peace diplomat in Styracodon custody convinces the Triceraton Republic that peace with Styracodons is impossible, and they recruit Mikey's help for a new war of genocide against the Styracodon race.