They are bipedal indigo dinosaur-like creatures with a nasal horn, fangs, and small, orange dragon wings, although they cannot fly. Rexes sport a few similarities to Yoshis, including their body shape and reddish shoes. Rexes have compressible bodies, as their stature becomes flatter when jumped upon.
In Super Mario World, a Rex simply walks slow in a single direction, but moves faster when stomped to half its size. In Mario & Luigi: Superstar Saga, a Rex's attack involves charging into Mario or Luigi. In the game's remake included in Mario & Luigi: Superstar Saga + Bowser's Minions, a Rex makes a high-pitched noise upon being stomped.
In Super Mario World[]
Mario encountering several Rexes in Yoshi's Island 1 in Super Mario World
Rexes are one of the first enemies encountered, as they first appear in Yoshi's Island 1, although they only appear in two other levels, Chocolate Island 2 and Awesome. A Rex has to be stomped twice to defeat it, with the first stomp only flattening them to half the size their height while increase their running speed. Alternatively, Mario or Luigi can instantly defeat a Rex by either Spin Jumping onto it, throwing a fireball at it while in their Fire form, hitting it with a cape in their Caped form, or touching it while under the effects of a Starman. Rexes are among the enemies that Yoshi can eat. Defeating a Rex earns the player 200 points.
Mario and Luigi battling a Rex and a Beanie in Mario & Luigi: Superstar Saga
Rexes are encountered at Hoohoo Mountain, exclusively in battles alongside Beanies and Dry Bones, and Mario and Luigi do not encounter any Rexes on the field. Like in Super Mario World, jumping onto a Rex decreases its height, but unlike said game, this does not instantly defeat it, and a Rex can even be hit again to further squish its body. When a Rex is flattened, the targeted Mario Bro can dodge the Rex's attack, because when a Rex is at its full size, it can neither be dodged nor countered, as it is too tall to jump over.
The items dropped by a Rex at the end of a battle depends on the method in which they were defeated. If a Rex was defeated from a Hammer attack or a strong enough Jump attack to defeat it in one hit, it drops a Syrup, but if a Rex is defeated while flattened, it drops a 1-Up Mushroom in international versions or a Green Pepper in the Japanese version. Rexes are healed from fire-based attacks.
Rexes return as enemies in the remake of the main game, but a difference from before is that Mario and Luigi can now counterattack a Rex while it is at their full size. Rexes also make high-pitched grunts when jumped on.
In the Minion Quest: The Search for Bowser campaign, Rexes appear as Melee troopers, and they attack by charging into opponents. Their Special Skill is Mega Tackle, in which the Rex charges even more quickly into an opponent, dealing more damage than what a regular charge can do. As an enemy captain, the Rex is silent when using Captain Command, with only an ellipses in its text box. Rexes are the only standard Mario enemies that cannot be recruited as allies.
Peach encountering a Rex in Fury Volcano 4-1 in Super Princess Peach
Rexes first appear in the levelFury Volcano 4-1. Rexes behave similarly as in Super Mario World, and similarly to said game, if Peach stomps a Rex, this squishes its body, and Peach can defeat it by stomping it again. Alternatively, Peach can instantly defeat a Rex by using any other attack, such as from swinging Perry at it.
Rexes were also given a variant named Sad Rex, which is imbued with the Gloomvibe. Jumping onto a Sad Rex turns it into a regular flattened Rex, which can be defeated using the same methods as their regular counterparts.
Rexes appear in a few episodes. In "Send in the Clown," Rexes were disguised as clowns for Bowser's circus trap. However, there they were just referred to as dinosaurs. A pack of similar-looking dinosaurs later appeared as chefs in "King Scoopa Koopa", although they cannot be the same as the Rexes, as they came in different colors.
• ⋆-Enemy, boss, or stat exclusive to the main game. • ⋆⋆-Enemy, boss, or stat exclusive to Minion Quest: The Search for Bowser. • ⋆⋆⋆-Enemy variants differ in Mario & Luigi: Superstar Saga + Bowser's Minions.
Bowser's Villa 8-1 • Bowser's Villa 8-2 • Bowser's Villa 8-3 • Bowser's Villa 8-4 • Bowser's Villa 8-5 • Bowser's Villa 8-6 • Bowser's Villa 8-7 • Bowser's Villa 8-8 • Bowser's Villa 8-9
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