In the opening miniseries, Krang and Shredder attempt to take over Earth using Krang's Rock Soldiers and Shredder's Foot Soldiers, but at the end they are defeated by the Ninja Turtles who send the Technodrome to Dimension X, alongside with Krang, Shredder, Bebop and Rocksteady inside it as Donatello reserves the portal flow.
Season 2 begins with Shredder returning to Earth, while Bebop and Rocksteady stay in the Technodrome before mid-season 2 sees them returning to Earth. Throughout season 2, Shredder usually remains on Earth while Krang stays in the Technodrome in Dimension X. Season 2 ends with the Technodrome returning to Earth in Return of the Technodrome, but the Ninja Turtles send it to the planet's core where it stays throughout most of season 3.
In the season 3 episode The Fifth Turtle, the Earth is one of the celestial bodies in the conjunction where Krang uses Capsidium crystals to re-power the Technodrome. Season 3 also sees the turtles visiting an underground cave, where dinosaurs still live.
Season 3 ends with the Technodrome returning to Earth's surface and Krang trying to send Earth into Dimension X, but instead the Turtles send the Technodrome there.
Season 4 sees the Technodrome on the Volcanic Asteroid in Dimension X. The Vacation in Europe sideseason, which also takes place during season 4, has the Ninja Turtles travelling across European countries, sometimes followed by Shredder and Krang, and sometimes facing other antagonists. Unlike season 2, however, many of these episodes see Shredder, Bebop and Rocksteady returning to Dimension X at the end.
In the season 4 episode Shredder's Mom, Shredder and Krang try to warm up the Earth in order to force its political leaders to surrender to them. During seasons 4 and 6, Filo Sopho twice tries to mess with Earth's orbit.
The Technodrome returns to Earth during early-season 5 in My Brother, the Bad Guy but the turtles and Shredder's brother Kazuo Saki, who has travelled all the way from Japan, trap it in the Arctic. In Rock Around the Block it falls to the bottom of the sea.
Season 7 ends with the Technodrome, in Shredder Triumphant!, returning to Earth's surface before the turtles send it empty to Dimension X, trapping Shredder, Krang, Bebop and Rocksteady on Earth.
During the last two seasons, Shredder and Krang remain trapped in Dimension X, while extraterrestrial warlord Dregg tries to conquer Earth by manipulating the people, letting them believe that he is an hero who came to save them. The Ninja Turtles unmask him and sent him to Dimension X in the final episode, Divide and Conquer.
However, Shredder, Krang and Dregg were not the only ones, many villains tried to conquer Earth or parts of it, but at the end the turtles stopped them.
- Brazil (Star of Brazil)
- Denmark (it's embassy to the USA)
- Sweden (Sven Svensson's native country)
- Vatican City