Rhyhorn is a rhinoceros-like creature with a body covered in gray, rocky plates. Its underside and rear are smooth, and it has four short legs with two claws on each foot. It has a triangular head with narrow, red eyes, two fangs protruding from its upper jaw, and small, triangular openings on the upper sides. A spiked ridge runs along its back, and it has a single short horn on the tip of its snout. The female has a shorter horn than the male. In addition to its rocky hide, its bones are a thousand times harder than human bones.
Rhyhorn's brain is very small, giving it a one-track mind. When it runs, it forgets why it started and continues until it falls asleep. However, it may recall the reason upon demolishing something. Rhyhorn runs in a straight line due to its short legs making it inept at turning. It does not care if obstacles get in the way, merely smashing through them or sending them flying. Sometimes it may feel pain the day after a collision. Rhyhorn lives in rough terrain.
The first Pokémon that Ash and his friends saw at Pinkan Island in In the Pink was a Rhyhorn, which was pink in color. Although initially unaware of the trio, Ash rushed up to it and antagonized it. It then cornered the gang at a cliff-edge, and attempted to charge at them, who were saved by Togepi using Teleport via Metronome, causing Rhyhorn to charge over the cliff. It was then rescued by Ash and friends with the help of the resident Officer Jenny.
Rhyhorn debuted in The Flame Pokémon-athon!, entering a race with its Trainer. Rhyhorn jumped onto a stone but they sank, and Rhyhorn and its Trainer were eliminated from the race.
Rhyhorn, the Spikes Pokémon. Rhyhorn recklessly charges straight ahead, trampling over anything that gets in its way.
In Pokémon Origins
Rhyhorn in Pokémon Origins
A Rhyhorn appeared in File 3: Giovanni where Giovanni sent it out for his Gym battle against Red. It took out most of his team and tied against his Hitmonlee.
In the manga
Rhyhorn in Pokémon Adventures
In The Electric Tale of Pikachu manga
Drake's Rhyhorn was only seen in a flashback. It is currently unknown whether or not he still has it.
Rhyhorn was one of the rental Pokémon used by Emerald in his Factory challenge.
A Rhyhorn belonging to Y debuted in An X-cuse to Come Out and Play. It was originally owned by Grace. It often carries X around while he sits inside a tent attached to its back. Much later, Y decides to officially keep Rhyhorn on her team, and nicknames it Rhyrhy.
In the Pokémon Zensho manga
Shigeru has a Rhyhorn which he caught in the Safari Zone.
Pokémon X and Y: In X and Y, the player's mother, Grace, is a retired Rhyhorn racer. Her Rhyhorn partner lounges outside her house. The player can ride it, but cannot take it outside the small front lawn. The player can ride another Rhyhorn on Route 9, which is the only way to cross the jagged, rocky terrain to Glittering Cave.
Rhyhorn runs in a straight line, smashing everything in its path. It is not bothered even if it rushes headlong into a block of steel. This Pokémon may feel some pain from the collision the next day, however.
Rhyhorn's brain is very small. It is so dense, while on a run it forgets why it started running in the first place. It apparently remembers sometimes if it demolishes something.
Rhyhorn runs in a straight line, smashing everything in its path. It is not bothered even if it rushes headlong into a block of steel. This Pokémon may feel some pain from the collision the next day, however.
Rhyhorn's brain is very small. It is so dense, while on a run it forgets why it started running in the first place. It apparently remembers sometimes if it demolishes something.
Rhyhorn and its evolutions are the only Rock-type Pokémon that belong in the Field Egg Group.
Origin
Its design appears to be inspired by an Indian rhinoceros, with similar plated armor, and an Uintatherium from whom it may have taken its flat head and horn, with elements of ceratopsids.
Name origin
Rhyhorn may be a combination of rhinoceros and horn. Rhy may also derive from the igneous rock called rhyolite, alluding to Rhyhorn's Ground/Rock type combination.
Sihorn is a combination of 犀 sai (rhinoceros) and horn.