Mesozoic Island is a former isolated island populated with Mobian dinosaurs and their real life counterparts along with other prehistoric life. It first appeared in Sonic: Dino-Emeralds and is the home for dinosaurs like Nikita the Raptor, Gogsa the Stegosaurus, Ochiai the triceratops, Hiki the Rex and her husband.
At some point during the Mesozoic period, a meteor containing the soon to be the dino-emeralds crashed onto the island and gave prehistoric dinosaur mobians intelligence, power and protection they needed. After have lived alongside the non-mobian dinosaurs and pterosaurs along with a few other primitive lifeforms for millennia until 65 million years, leaving the remaining Dino mobians and a few non-mobian dinosaurs and other prehistoric animals alive on the island, living alongside them as pets, cattle and even worker animals.
They lived isolated on the island for millions of years, with the emeralds protecting them by consealing the island in a barrier.
When Sonic and his team came to the Island after Tails found the signature of the emeralds on the Island by his radar, they soon learned about how the dino mobians and the other creatures remained unchanged during all years by the help of the Dino emeralds keeping the nature alive and as well giving them the knowledge of all language. The king of the island, King Giganoto was first hesitant to allow outsiders on the island but soon changed his mind when Noire the Lioness, Cyo's cousin convinced him to let her show them around.
As they have been sightseeing the island they soon discovered that Agent Shinu has been sent for a mission to steal the Dino emeralds to Eggman as well some dinosaur eggs to create an army out of mechanically modified dinosaurs, though they manage to foil their plan when Sonic transformed into a Super raptor by the dino emeralds with the help of Nikita and Ochiai.
As a reward for saving the Island, Giganoto ceases the isolation of the island to allow anyone to visit it.
- Saurian town - capitol and only city on the island
- Fishfalls - Here goes many to catch fresh fish.
- Sauropod forest - Notable for it's populations of many sauropods like Argentinosaurus and Brachiosaurus.
- Lake Deino - the second largest lake of the island
- Lake Iguana - Smallest lake on the island
- Lake Megalo - Largest lake of the island
- Mt. Deathclaw - The dormant volcano of the island, latest eruption when Pyrah (Blaze's clone) became a gigantic lava golem.
- Iguana hill - second highest point of the island
- Mt. Mesozoic - The highest mountain of the island, this is where the Dino Emeralds are kept.
- Dino Emerald Altar - on top of Mt. Mesozoic and there Gogsa the Stegosaurus guards the emeralds.
- King Giganoto's palace - This is where King Giganoto live at.
- The Island itself and it's highest mountain is named after the Mesozoic era.
- Mesozoic Island is the one place Cyrox dies at the hands of Deinonychus.