Rudy is the main antagonist of Blue Sky's 5th animated feature film, Ice Age: Dawn Of The Dinosaurs (even though he is not seen until the end), and its subsequent video game. He is a rogue albino Baryonyx and Buck and Momma Tyrannosaurus Rex's archenemy and the top predator in the dinosaur valley. He is very responsible for scratching out Buck's eye and constantly tracks the weasel, hoping for revenge on Buck for plucking out his tooth, leaving him with a scar on his lip.
Rudy is a vicious, sadistic, truculent, aggressive, devastating, and bloodthirsty opponent in the eyes of Buck and the other dinosaurs. He is a gigantic albino Baryonyx with red eyes and a long jaw. He has sharp claws on his hands and feet and sharp teeth, missing the one that Buck knocked out. He is shown to be very brave, cruel, greedy, fierce, violent, sarcastic, predatory, and relentless.
Ice Age: Dawn of the Dinosaurs
Before the film takes place, Rudy attacks Buck the weasel, scratching out his eye. He then eats Buck but before he can swallow him, Buck manages to escape the dinosaur's rockets out of the dinosaurs mouth, knocking out one of his teeth.
During the movie, Rudy, until the climax, was only seen in the shadows to show his evilness and massive appearance. He follows the tracks of Buck and the herd, planning to ambush them at the right moment. Buck (as well as Momma) occasionally hear his loud roars coming from the forest. He manages to catch up with Sid, accidentally left behind by Momma. The terrified sloth is able to escape from Rudy by running into an obsidian river. Before walking away, Rudy stomps on the ground, causing the lava underneath to reemerge and trap Sid, only to be saved by Buck and the possums before falling down a lava waterfall.
At the end of the movie, once Sid is saved, Rudy ambushes Buck, Manny, Ellie, Diego, the possums, and newborn baby Peaches inside the cave they used to travel to the dinosaur world and attempts to eat them all. Buck distracts Rudy as Manny, Diego, and Sid tie Rudy up with vines. Sid accidentally trips over the wire, allowing Rudy to get back up and presume chase. Before Rudy is able to finish his nemesis and his friends, Momma, in a timely arrival, charges into Rudy and pushes him off a nearby cliff, sending him plummeting down to his apparent death. Buck is shown to feel sorrow for Rudy, because the only challenge in his life was gone. However, it is later shown that Rudy survived the fall, and continues his feud with Buck, who starts to ride him (much to Rudy's chagrin).
Ice Age: Continental Drift
Rudy, alongside Buck, makes a cameo appearance in Ice Age: Continental Drift and Scrat's Continental Crack-Up Part 1, where Buck is seen riding Rudy by Scrat as he descends to the Earth's core.
Rudy is the final boss of all of the versions of Ice Age: Dawn of the Dinosaurs. Momma and Buck fight against Rudy in his cave hideout while Manny and his gang run for shelter. As Momma fights Rudy head on, the player controls Buck as he uses his bamboo launcher to destroy rafflesia flowers connected to vines holding on to a rock column dangling above Rudy and Momma. As Buck attacks the rafflesias, he can use his whip to pull down the vine attached to the rafflesia, causing small parts of it fall onto Rudy, angering him, and attempts to bite Buck. Once the last rafflesia is destroyed, the complete rock column falls near Rudy, partially blinding him with dust and pushes him toward the edge of the cave cliff. Momma shoves Rudy off the cliff similar to the movie, but he also survives the fall.
- Rudy is a parody of Moby Dick. Both are great white beasts who mutilated their respective enemies; Buck (who lost an eye) and Captain Ahab (who lost a leg).
- Rudy is the only Ice Age villain to appear in more than one film, due to his cameo in Ice Age: Continental Drift.
- Due to his immense size, Rudy is considered the strongest villain in the Ice Age franchise.
- Rudy is one of the most dangerous Ice Age villains in the franchise.
- Rudy is the first main Ice Age villain not to die of his respected movie. Captain Gutt, the main antagonist of the next movie Ice Age: Continental Drift, could've survived his fate, but it is uncertain if he did or not.
- He is also the second main antagonist of a Blue Sky Studios movie who doesn't die in his respected movie, the first being Sour Kangaroo.
- Rudy bears a resemblance to the Albino Giganotosaurus from Journey to the Center of the Earth (2008), the Indominus rex from Jurassic World and the Screaming Death from Dragons: Defenders of Berk due to their white skin and other features.
- Rudy appears as a giant two-legged albino crocodile due to the fact Baryonyx is a species of Spinosaurus, which have heads like those of crocodiles.
- Rudy is similar to the Dinocroc from the 2004 sci-fi film of the same name and its 2011 sequel, Dinocroc vs. Supergator, as well as the Sarco Brothers from the 2012 Korean film, Dino Time (released in America as Back to the Jurassic).
- Rudy did not appear nor was mentioned by Buck in Ice Age: Collision Course, despite the latter having a major role in the film. It is unknown where Rudy is, as when Buck is first seen, he is not battling him but three dino birds named Gavin, Roger and Gertie. It's possible that Rudy died of old age.