Tyrannosaurs are a family of coelurosaurian theropod dinosaurs which comprises two subfamilies containing up to six genera, including the eponymous Tyrannosaurus Rex. Tyrannosaurus Rex is a fixture in popular culture around the world. T-Rex is commonly considered the most famous dinosaur and may well be the most popular. For many years it was regarded as the largest land predator to ever life, being recently eclipsed by other large carnosaurs like Giganotosaurus and Spinosaurus, however it is still thought of at the quintessential killer dinosaur by many. This has made Tyrannosaurus a popular basis for many zoids.

In the early days of zoids, creating zoids of a tyrannosaur's scale was all but impossible. As a result their designs often focused on performing as easy to produce and adaptable platforms. As time passed technology improved and today Tyrannosaur zoids are frequently behemoth creations, slow and lumbering with an abundance of firepower. Many Republic Tyrannosaurs are capable of mounting supercannons while Imperial Tyrannosaur-Types are almost uniformly equipped with Guylos Charged Particle technology. Despite this, in recent times the empire in particular has realized the value of combining the Tyrannosaur's ferocity and power with speed and as time has passed, Tyrannosaur zoids have become more well rounded and generally more deadly. Just as they were on earth 65 million years ago, the Tyrannosaurs are the Apex predators of Planet Zi.