Bronolyth is a gigantic sauropod Pokemon with symbiotic seeds inside its skin that produce a layer of foliage over its skin. Due to eating stones as Magyora and Ampelore, it has armor all over its body made up of rocks, with hard spikes on its back and rock plates on its neck and tail. Its bush is predominately green with dark green chin and back foliage, while its rock plates are darker gray than those on Ampelore. Its eyes are now hidden in black sockets, though the red-brown irises can still be seen up close. Its feet now have three claws each, and are covered with grey rock armor that resembles the columns of some ancient temples.
Like its pre-evolutions, Bronolyth can and will use its plant qualities to its advantage. It can throw Razor Leaf with the leaves in its outer layer of brush, and its long neck also functions as a cannon, allowing it to use Bullet Seed, SolarBeam, and Flash Cannon. It can also use several Rock type techniques such as Rock Throw, via either hitting a rock with its tail upwards as to hurl it at an attacker or shake off one of the rocks on its body and hurl it at the foe, or Rock Polish, via rubbing its brush against the rocks embedded it is skin as to reduce wind resistance. Because of its prehistoric roots, its repetoire of special techniques also includes AncientPower and some Ground-type moves like Fissure, as well as a few powerful Steel-type moves like Iron Tail.
Bronolyth has the ability Overgrow, the signature ability of all Grass type starter families. This allows it to boost its strength when its health is low.
Bronolyth, like their pre-evolutions, are rather scarce in the wild. They are very hard to find so they are bred in breeding centers for Professor Parcel as starters. They are found in herds in the wild, travelling through plains and forests with their young and frequenting grazing sites far and wide in annual migration trips.
Bronolyth can get food from the photosynthetic cells in its brush to gather energy and food. Otherwise, it grazes on grass, fruit, and tree leaves. Its long neck allows it to reach to the highest trees where the leaves and fruit are the tastiest.
Iron: "Its massive body is made of ancient rocks, darkened by the passing of time. Its back is covered by by a soft cloak of leaves and weed, but underneath there is a layer of long sharp rock needles, which protects it from attacks by many predators, which bite the bush over them and pay dearly for it. Due to its large size and hard body, it has few predators; its only real threat is the powerful Py-Rex, and even then conflicts between the two are rare."
Copper: "Its massive body is made of ancient rocks, darkened by the passing of time. Its back is covered by by a soft cloak of leaves and weed, but underneath there is a layer of long sharp rock needles, which protects it from attacks by many predators, which bite the bush over them and pay dearly for it. Due to its large size and hard body, it has few predators; its only real threat is the powerful Py-Rex, and even then conflicts between the two are rare."
Bronze: "With its ancient rock-hard armor and the leaves and ivy covering its body, Bronolyth is often mistaken for some ancient monument or fortress. Like a fortress, this gigantic Pokemon specializes in defense, and can take hits from anything without even moving before finishing the battle with a single blow from its massive tail. Its only threat, and nemesis, is the equally gigantic Py-Rex, the only predator that can bite through its spiked armor."
Bronolyth, like its pre-evolutions and Chikorita's line, has many characteristics in common with the sauropod dinosaurs. Specifically it is based on Argentinosaurus, the largest of the dinosaurs. Its habit of eating rocks may be a reference to the practice of consuming gastroliths in many real-life sauropods, while its rock armor may be a reference to titanosaurs such as Saltasaurus.
Bronolyth comes from "Brontosaurus" and a mispelling of "monolith." While "Brontosaurus" is an outdated name, it is frequently used as a name for any generic sauropod dinosaur. "Monolith," meaning a large monument often made of stone, refers to its massive size and Rock-type.
Its Japanese name comes from Apatosaurus, the modern name of "Brontosaurus," and yusaburu, "rock".