Althought Diego is one of the main heroes of the Ice Age franchise, he was a villian in the first movie although he later reformed and became ahero for the rest of the franchise.
Role in the first film Edit
In the first film, he was part of of a pack of saber-toothed cats led by Soto, their vicious leader who hated a tribe of human hunters for killing half of their pack. Diego was tasked with getting a human baby from a tribe of humans so that Soto would have his revenge on the humans by killing the baby to send the humans a message they would never forget. Diego, however, failed to retrieve the baby due to the mother's intervention and self-sacrifice. Soto then ordered Diego to get the baby or face being killed by his own pack if he failed again. Diego then encountered Manny and Sid, who had already found the baby before he did. Diego then volunteered to lead both the baby and Manny to Glacier Pass, while secretly leading them to his pack at Half Peak to kill them. But after Manny risks his own life to save him from falling into a river of lava, Diego has a change of heart and then tells Manny and Sid of his pack's plot, blowing his own pack's cover. In a fit of rage, Manny pins Diego to a rock wall with one tusk, and pressed the other tusk's point against Diego's throat, intending to kill the saber-tooth. Diego pleads for Manny to trust him as he forms a plan. However, the plan goes wrong as Soto appears around the corner, inviting Diego to help kill Manny. At first, he appears to side with Soto, growling at Manny. But then he stands in front of Soto, and coldly told him to "Leave the mammoth alone." Oscar and Lenny, (Who had been unconscious at the time), attack Manny. Diego then fights Soto (the scene could be compared to when Simba fights Scar in The Lion King). Diego ends up severely wounded after intercepting Soto's attack. Manny then knocks Soto into a wall and icicles fall and impale him to death. The seemingly dying Diego tells the herd to leave him before they lose the humans, sacrificing himself to ensure the baby's return. However, in the end, Diego recovers from his injuries and catches up with Manny and Sid in time to say his last heartfelt goodbye to the baby and happily decides to head south with them.