The fifty-first episode of Adventures of Sonic the Hedgehog, and the fourth and final part of the "Quest for the Chaos Emeralds" saga.
Robotnik, Scratch and Grounder travel back to the Mesozoic Era and steal the Chaos Emerald of Life. Sonic tries to stop them, but Robotnik succeeds in collecting all four Chaos Emeralds and becomes the Supreme High Robotnik.
This episode provides examples of:
- Added Alliterative Appeal: When they arrive in the Mesozoic Era, Robotnik advises Scratch and Grounder to bring the Dinosaur Detection Device.
- Appease the Volcano God: To get the Chaos Emerald of Life from the volcano, Robotnik must first make a sacrifice to Magma the Volcano God. Scratch and Grounder are the sacrifices, but since the supposed lava is actually volcanic mud, they survive.
- Art Initiates Life: The Chaos Emerald of Life can invoke this, creating anything like Magma Men.
- Asteroids Monster: Sonic cuts through the Magma Man that Robotnik summons to attack him, but this creates a second Magma Man.
- Attack of the 50-Foot Whatever: Robotnik succeeds in collecting all four Chaos Emeralds and becomes the Supreme High Robotnik to take over Mobius.
- Be the Ball: Early in this episode, true to his video game counterpart, Sonic shapes himself into a ball and is used as a volleyball by a colony of Beach Bunnies.
- Caused the Big Bang: The Big Bang is seen as a huge stick of lit dynamite in space.
- Chest Monster: When Robotnik revisits Shark Island, he uses his Robot Transmogrifier Ray to turn the treasure chest housing the Chaos Emerald of Invisibility into a crab-like robot to trap Sonic.
- Cool Board: In this episode, Professor Caninestein invents the Time Travelling Skateboard from a modified Time Warp Boogie Board to make it smaller and faster.
- Crazy-Prepared: When Robotnik creates an army of Magma Men to attack Sonic, Tails, and the Cave Bears, he has them toss them into the volcano, and to ensure that Tails can't fly to safety, he ties Tails' tails up.
- Gentle Giant Sauropod: Hilariously subverted when a Brontosaurus steps on Scratch and Grounder and walks off with them still stuck to its sole.
- Giant Foot of Stomping: Scratch and Grounder have a sudden encounter with a Brontosaurus this way.
- Help Yourself in the Future: Sonic revisits each destination before he got there the first time to meet up with himself so they can team up and stop the Supreme High Robotnik.
- Here We Go Again!: Robotnik travels through the previous time periods to get the remaining three Chaos Emeralds.
- Hobbling the Giant: When Sonic and several temporal clones of him return to Mobius in the present day to stop the Supreme High Robotnik, Robotnik creates a metal monster from a nearby pylon. The Sonics cut off its feet, causing it to lose its balance and fall over.
- Hoist by His Own Petard: Robotnik roboticizes a T. rex to attack Sonic, but Sonic manages to take control of it and use it to attack him, Scratch, and Grounder.
- Hollywood Prehistory: There are Brontosaurus, Tyrannosaurus, Pteranodon and caveman-like bears living at the same time, 75 million years ago.
- I Have Your Wife: When Robotnik revisits King Arfur's Kingdom, King Arfur refuses to surrender the Chaos Emerald of Invincibility to him. Scratch and Grounder threaten to attack Gwendolyn unless he surrenders the Emerald, so he reluctantly does.
- Laser-Guided Karma: In this episode's "Sonic Says" segment, Robotnik re-attempts his plan to collect the Chaos Emeralds with Sonic's time-travel skateboard, since Sonic's temporal clones have taken his time machine to return the Chaos Emeralds to their rightful destinations, then destroyed it afterwards. However, he takes the skateboard from Tails as he tries to modify it to make it faster (which Sonic advises against doing to the viewers), which results in the skateboard electrocuting him.
- Magma Man: Robotnik uses the Chaos Emerald of Life to create them to attack Sonic, Tails, and the Cave Bears. However, the lava is actually volcanic mud, which explains why Sonic is able to attack them without burning up.
- Mythology Gag: The robot that Robotnik creates from the treasure chest housing the Chaos Emerald of Invisibility resembles Crabmeat from Sonic 1.
- Near-Villain Victory: Robotnik succeeds in collecting all four Chaos Emeralds and becomes the Supreme High Robotnik. It takes Sonic and Tails teaming up with several temporal clones of themselves to defeat him.
- Never Say "Die": Averted. Robotnik outright says “Nice try Hedgehog. But as fast as you can kill them, I can bring them back to life!” In reference to his lava monsters.
- One-Winged Angel: Robotnik transforms into the Supreme High Robotnik as a result of successfully collecting the four Chaos Emeralds, and Sonic, Tails, and their temporal clones have to defeat him.
- See the Invisible: During the final battle with the Supreme High Robotnik, Robotnik uses the Chaos Emerald of Invisibility to make himself invisible. Tails and several temporal clones of himself dump bags of flour on Robotnik to expose him.
- This Is a Drill: When Robotnik revisits Shark Island, Grounder puts a drill on his nose (even though his nose is a drill!) to dig up the treasure chest housing the Chaos Emerald of Invisibility.
- Time Travel Episode: This episode is the fourth and final part of a four-episode arc involving time travel. A prehistoric island takes up the first act, and the destinations of the previous three episodes (Robotnikhotep's Tomb, King Arfur's Kingdom, and Shark Island) are briefly revisited in the second.
- Timey-Wimey Ball: In the previous three episodes, Sonic and Tails defeat Robotnik in several different eras, keeping the Chaos Emeralds out of his hands. Robotnik, in a rare flash of ingenuity, revisits time periods and grabs the Emeralds anyway. Sonic and Tails defeat him by traveling through time to the same time until about a dozen temporal clones of each have assembled, totally smashing any pretense of a Stable Time Loop in the process. The whole thing gets Lampshaded when Tails is shown scratching his head when Sonic explains his plan.
- T. Rexpy: Played with; Robotnik turns a Tyrannosaurus into a robotic one.
- Unwilling Roboticization: Robotnik uses his Robot Transmogrifier Ray on a T. rex to get it to attack the clan of Cave Bears that attack him, Scratch, and Grounder, and later, Sonic. He later uses it on a pterodactyl so it will take him to the Chaos Emerald of Life, and on the treasure chest housing the Chaos Emerald of Invisibility to trap Sonic when they revisit Shark Island.
- Wingding Eyes: The Crab Robot's eyes turn into hearts when he sees a female crab.
- You Have Outlived Your Usefulness: Robotnik sacrifices Scratch and Grounder to Magma the Volcano God to get the Chaos Emerald of Life, but since the supposed lava is actually volcanic mud, they survive.
