Tyrantrum is a bipedal, dinosaurian Pokémon that resembles a large theropod. It is predominantly brownish red with scaly patterns on its skin and scattered orange highlights on some scales and ridges. Tyrantrum's head is proportionately large with a blunt, ridged snout and powerful jaws. It has black around its eyes and a light gray lower jaw covered by a beard of white, primitive feathers. Several sharp teeth are visible in the lower jaw, while the upper jaw is lined with orange-tipped, tooth-like projections. Over its eyes is a row of five spikes resembling a crown. Around Tyrantrum's neck is a feathery white ruff that extends over its shoulders similar to a cape. Its underbelly is gray with white borders and there are two orange spikes near the tip of its long tail. Its small forelimbs have only two black-clawed digits each, but it has powerful hind legs with three black claws each. Plated, armor-like ridges cover its knees, back, and the top of its tail.
Before its extinction 100 million years ago, Tyrantrum was known to be vicious but had the presence of a magnificent king. Its powerful jaws, capable of shredding thick metal plates like a car, made it invincible. It is theorized that its original form was completely covered with a feather-like coat. Tyrantrum preys on Amaura.
Four Tyrantrum debuted in The Tiny Caretaker!, under the ownership of several Scientists, with one of them having evolved from a Tyrunt. Bonnie hoped Clemont would catch the Tyrantrum she had befriended, but because the Scientists owned it, she had to bid a sad farewell to it.
Tyrantrum reigns like a king over the other land-dwelling prehistoric Pokémon around the volcano. It’s completely unguarded when it sleeps—probably because it’s so strong that it feels no need to be cautious.
Tyrantrum shares several aspects with Aurorus. Both are Rock-type Pokémon introduced in Generation VI. Both of them evolve starting at level 39 from a Pokémon with a base stat total of 362, although Tyrantrum evolves at day instead of during the night. Both also share a base stat total of 521.
Tyrantrum is based on the genusTyrannosaurus, though it also shares some characteristics (such as the orange facial crest) with members of the Carnosauria clade. The crest is also similar to those seen on Cryolophosaurus. Additionally, the crest and white feathers are inspired by the image of kings, with the crest acting as the crown, the fringe on the lower jaw acting as a beard, and the fringe on the neck acting as a cape lined with fur. The fringe is also derived from the theory that Tyrannosaurus supposedly had feathers.
Tyrantrum may be a combination of Tyrannosaurus or tyrant and tantrum.
Gachigoras may be a combination of ガチガチ gachigachi (teeth chattering), ガチ gachi (serious or for real), ガチン gachin (banging noise), がっちり gacchiri (stocky), and Chigoras (Tyrunt).
In other languages
From ガチガチ gachigachi, ガチ gachi, ガチン gachin, がっちり gacchiri, チゴラス Chigoras, and Tyrannosaurus