201–145 million years ago During the Jurassic period. North America was far different from what we see today. The mid era of the dinosaur. The time long before infamous T-rex existed. The lands covered lush green forest and meadows. This was not only a world where nature and species are highly diverse but also a cruel and harsh place where only one can survive. You can be whatever you wished either be some time traveler stranded in this strange place or be a dinosaur yourself

(Known dinosaur species present in this era)

[Sauropods (Giant Herbivores)]

Apatosaurus

Diplodocus

Brachiosaurus

Camarasaurus

Barosaurus

Haplocanthosaurus

Supersaurus

Brontosaurus (sometimes considered same as Apatosaurus)

Armored Herbivores

Stegosaurus

Hesperosaurus

Gargoyleosaurus

Ornithopods (Small to Medium Herbivores)

Camptosaurus

Dryosaurus

Nanosaurus

[Theropods (Carnivores)]

Large Apex Predators:

Allosaurus

Torvosaurus

Ceratosaurus

Medium / Small Predators:

Ornitholestes

Coelurus

Marshosaurus

Stokesosaurus

Tanycolagreus

Early Mammals

Morganucodon

Docodon

[Fruitafossor (small insectivore)]

Paurodon

[Pterosaurs (Flying Reptiles)]

Rhamphorhynchus

Pterodactylus

Mesadactylus

[Crocodylomorphs & Other Reptiles]

Goniopholis (semi-aquatic crocodylomorph)

Hoplosuchus (small terrestrial crocodylomorph)

Macelognathus (small croc-line reptile)

Turtles & Amphibians

Glyptops (freshwater turtle)

Kayentachelys (early turtle)

Eocaecilia (early amphibian/caecilian)

[Fish & Aquatic Life (if you want total ecosystems)]

Semionotus (ray-finned fish)

Lepidotes (ganoid fish)

Hybodus (shark-like fish)

[Invertebrates (commonly fossilized)]

Ammonites

Belemnites

Freshwater bivalves and gastropods