The Chozo Ruins are the remains of a great civilization that Samus visits in Metroid Prime and one of the main areas on Tallon IV along with Tallon Overworld, Magmoor Caverns, Phendrana Drifts, and the Phazon Mines.
At an unspecified point in history, Chozo settlers left their home planet of Zebes and colonized Tallon IV. These colonists made a conscious decision to abandon their technologically advanced lifestyle and live in harmony with nature, and their descendants left behind lore to honor their legacy. Consequently, they constructed what later became the Chozo Ruins with simple materials, forming their city's architecture around the natural landscape: buildings were hewn from stone, bridges were woven with branches, halls followed watercourses and chambers surrounded ancient trees. In the deeper portions of their city, they built sentient statues in their likeness, as well as other non-sentient sculptures for purposes decorative and otherwise. Several years after the initial settling began, the Chozo began developing new senses that allowed them to glimpse the future, an evolution that they believed to be a sign of their "harmonization with the infinite;" in these visions they foresaw the coming of a Worm that would destroy their world.
Scan data in the Ruins indicates that the structures of Chozo Ruins are ancient and cannot be dated by regular scientific methods. In addition to the trademark simplistic, unobtrusive, natural materials that make up the Ruins, and the extreme delicacy used to avoid upsetting the preexisting environment, other distinctive Chozo designs make them unique. Smooth, carved Half Pipes, testaments to the painstaking craftsmanship of Chozo builders, appear in several chambers. Mammoth, sometimes luminescent, etchings of ancient Chozo runes are situated decoratively on walls, platforms, and floors throughout the Ruins. Complex Runic Symbols and translucent, runic Holobanners capable of producing nonpolluting, self-sustaining illumination are also found here. Other sources of light include small, blue orbs embedded in walls.
While the Chozo on Tallon IV chose to live without advanced technology, metal hallways connecting two areas through large rock masses are sometimes used, and hallways lined with large pipes venting steam evidence some sort of steam powered system in the area, though its function is not specified. Decorative Radiation Collectors provide solar power to the Ruins as well.
A meteor impact on Tallon IV led to the spread of a Great Poison over the planet's surface, corrupting the ecosystem and mutating the wildlife. One of the mutated creatures took root in their sacred fountain, poisoning the water supply of the city. The Phazon corruption even led to hauntings by Chozo Ghosts, called by their fellow Chozo "The Turned" - entities that know no reason beyond the instinctive urge to protect Chozo lands. The Chozo contained the spread of the Poison with the construction of the Cradle but could not destroy it, and so the survivors left knowledge and technology for the Entrusted One they had glimpsed in their visions and abandoned the planet for good. Time and the Great Poison continued to erode the city until it became overgrown ruins.
When Space Pirate scans detected the energy radiating from the Phazon in the Impact Crater, they came to Tallon IV to investigate. After attempts to breach the Artifact Temple proved unsuccessful, the Space Pirates turned their attention to the Chozo Ruins, hoping to acquire the Artifacts required to unlock its seal. Chozo Ghosts ruthlessly attacked the Space Pirates who came to study the Ruins, which they intended to destroy afterwards, causing several casualties.
The Chozo ruins as they exist when Samus arrives are filled with hazards from the lingering Great Poison. Most of the water in the ruins is poisonous and deals damage to Samus when she comes in contact with it as a result of contamination. The water purifies after the defeat of Flaahgra, the mutated plant that is the source of the toxic water. Local foliage with basic sentience consists mostly of Tangle Weeds, Venom Weeds, and Blastcaps, plantforms that are well suited to the barren landscape. Ancient trees with gnarled branches and unnaturally withered leaves have suffered, even on the cellular level, from the contamination, but managed to stay alive; other plantforms adapted to thrive in the toxic environment.
The abandoned structures and courtyards are home to a wide variety of common creatures, including Beetles, who burrow in the warm sands, and the more ferocious Plated Beetle. The hives of War Wasps, Barbed War Wasps, and Ram War Wasps litter the crevices of the ruins. Immobile Eyons sit on the walls of tunnels, and Scarabs, which travel in large swarms, inhabit similar areas. Stone Toads, which are usually non-aggressive, can sometimes be found where there is water nearby. Shriekbats hang from ceilings, and rock-dwelling Reaper Vines embed themselves in cliff faces and walls. Light-emitting Plazmites stalk abandoned hallways looking for prey. Other lifeforms that inhabit the Ruins include Plated Puffers, Plated Parasites, Pulse Bombus, and Oculus.
 Obstacles and Acquisitions
Chozo Ghosts continue to haunt many religious sites after the purification and respawn after Samus leaves a room in which they abide, attacking her at every opportunity. Other unnatural enemies she encounters here include the Hive Mecha and the Incinerator Drone, both of which protect an upgrade; the other creatures defending upgrades are a Plated Beetle and Flaahgra.
The Chozo Ruins contain the most upgrades in the game, as well as five Energy Tanks and nineteen Missile Expansions. The area also has the vast majority of the Chozo Lore on Tallon IV by a wide margin: twelve entries out of sixteen. The Artifacts that are found in the Ruins are Lifegiver, Wild, and World, tying it with Phendrana for the most Artifacts in any area.
- "The history of the Chozo stretches back into ancient times, so far into the fog of the past that we know not where our ancestors came from. One thing is clear, however: the Chozo who colonized Tallon IV made a conscious choice to eschew a civilization of advanced technology. They chose to live in harmony with nature, guided by the providence of the universe. As this city grows, we plan to honor them with written tributes, carvings etched in stone to remind us always of their legacy." —Chozo Lore "Beginnings" - PAL version (Metroid Prime)
- "These large branches have been forcibly intertwined, forming what looks to be a bridge structure." —Scan Data (Metroid Prime)
- "Our home here on Tallon IV will be a place of simplicity: structures hewn from the stone, bridges woven with branches, hallways caressed by pure waters. We build around the ancient and noble trees, drawing from their strength and giving them our own in return." —Chozo Lore "Purification" - PAL version (Metroid Prime)
- "Identified as statue of Chozo Elder. According to Chozo lore, these statues served as the watchful guardians of tombs and shrines. Its outstretched hands are empty, as if awaiting an offering." —Scan Data (Metroid Prime)
- "Many long years have passed since we Chozo first took root in this land. The passage of time has always been a source of fascination to us; it is the belief of many Chozo sages that the truths of the universe hide within the tumbling currents of time's flow. Even as we search for answers there, however, we find illumination in other, unexpected places. We know not how the ability has come to us, but recently many Chozo have begun to sense things beyond the realm of ordinary perception. Strange sights and inexplicable sensations flood our minds, filling us with visions of past and future. We take this growing ability to be a sign of our burgeoning harmonization with the infinite; perhaps, finally, the universe's secrets are becoming known to us." —Chozo Lore "Harmonization" - PAL version (Metroid Prime)
- "Many Chozo are gifted with the distant sight, and even more begin to learn it as our harmonization with the universe becomes more and more complete. We peer forwards, seeing prophecy in the ripples of the water, hearing rumors of coming days on the breath of the wind. Though we celebrate the distant sight, many of these visions are dark - the worst of the prophecies, and the most common, tells of the coming of the Worm. Born from parasites, nurtured in a poisoned womb, the Worm grows, devouring from within, until the world begins to rot." —Chozo Lore "Worm" - PAL version (Metroid Prime)
- "These pillars have collapsed from erosion. Carbon dating cannot determine he age of these structures." —Scan Data (Metroid Prime)
- "Walls appear to have been constructed with extreme delicacy around tree limbs." —Scan Data (Metroid Prime)
- "Chozo runes translated. Holobanner text reads 'The Hall of the Elders.'" —Scan Data (Metroid Prime)
- "These blue orbs seem to be simple light sources." —Scan Data (Metroid Prime)
- "Chozo sculpture crafted in honor of Tallon's star." —Scan Data (Metroid Prime)
- "An ornate wall hanging with a highly reflective surface. It does not appear important." —Scan Data (Metroid Prime)
- "This etching resembles a birdlike creature." —Scan Data (Metroid Prime)
- "Radiation collector designed to absorb and store solar energy. They appear largely decorative." —Scan Data (Metroid Prime)
- "Unforeseen by sages, a meteor came as if from nowhere, casting a dark shadow of debris over the land with the violence of its impact. Its destructive force spent, the fallen star burned itself out rapidly, and the incident should have faded into memory...but the meteor brought with it corruption. A Great Poison burst forth into the land, a strange energy that clawed at natural life with a ferocity that seemed almost sentient. Bound by our ignorance of this phenomenon, we Chozo could only watch in horror as this dark force slowly began to spread across the surface of Tallon IV." —Chozo Lore "Meteor Strike" - PAL version (Metroid Prime)
- "The cries of this dying land echo in our ears as we Chozo watch the Great Poison seep ever further into the living pulse of the planet. The dark energy sinks into the trees and waters, devouring all life. Peaceful beasts die by the thousands - some creatures survive, but their forms grow as twisted and evil as the force that fell from the sky. Many of these mutated monstrosities remain small enough to do little harm, but others grow enormous and threaten our very existence. One such beast defiles our sacred fountain, disgorging poison from its foul form, replacing pure, flowing water with cascades of creeping death." —Chozo Lore "Spreading Evil" - PAL version (Metroid Prime)
- "So many creatures suffer beneath the blight upon the land, and we Chozo are no exception. But for all of our pain, we can at least believe in the promise of the future; unlike the apparitions that have begun to appear, entities that feel neither hope nor solace. We call these doomed souls The Turned - taking ghostly Chozo forms, they know no reason beyond the instinctive urge to protect our lands. They will likely exist in limbo forever." —Chozo Lore "Entrusted One" - PAL version (Metroid Prime)
- "None know if our temple, the Cradle, will prove powerful enough to contain this evil forever. For now, it wraps around that abomination, cutting it off from the world above. But how can we Chozo hope for the Cradle to remain intact when that which it guards writhes in the darkness, growing always stronger?" —Chozo Lore "Cradle" (Metroid Prime)
- "Things bound to earthly shapes are temporal and frail; existing in a single dimension, they are fragile, vulnerable, and ultimately mortal. However, not all things obey this law - shapeless, they wait beyond the realm of perception, emerging only when one arrives who can feel their presence. Such is the will of the Chozo. Our will to defeat the evil seeping into this planet remains forever, desiring only to see the darkness meet its end. Mindless but strong, our will shall never sleep until the Entrusted One arrives to cleanse this land." —Chozo Lore "Shapeless" - PAL version (Metroid Prime)
- "Planet Tallon IV, formerly a Chozo colony, was struck by a stellar object 50 years ago. Object was later determined to contain large quantities of Phazon. The Chozo were able to stave off the spread of Phazon, at the cost of many Chozo lives. The survivors abandoned the planet, fleeing to an unknown location. Decades later, Hunter Samus Aran responded to a distress call in the sector and discovered a Space Pirate Phazon Mining Station there. Aran eliminated both the pirate and Phazon threat from the planet, though not without cost." —Galactic Federation Data "Tallon IV Incident" (Metroid Prime)
- "Scans of the Spiral Sector detected a massive energy spike emanating from a Wanderer-class planet identified as Tallon IV. Scout reconnaissance was immediately dispatched to the center of the spike, a land mass at heading mark 40.08.02, returning with planetary samples and atmospheric imaging. Analysis shows the energy source to be an unstable radioactive material of enormous potential. We are unable to form an accurate risk-assessment at this time, but we are unlikely to find an energy source this powerful again. Analysis will continue, but currently Tallon IV appears to be a viable secondary headquarters." —Pirate Data "Contact" (Metroid Prime)
- "Results are in from field studies on extinct bioform group Chozo. We believe that Tallon IV was once a stronghold in a great Chozo empire, brought low by the meteor strike. Planetary devastation brought an end to the Chozo, yet remnants of their society remain. We are studying these relics in attempt to harness their power. What is of no use to us, we destroy. In time, we shall have all we need from this dead race, and shall wipe this planet clean of their ugly Ruins. The dead should serve the living, not hinder them." —Pirate Data "Chozo Studies" (Metroid Prime)
- "There have been numerous incidents involving spectral entities at Chozo Ruins sites. Several personnel have been assaulted by these Chozo Ghosts; few have survived. Survivors speak of swift attacks from nowhere, brief sitings of the enemy, then nothing, only to be followed by another attack. Science Team believes these attacks are in response to our efforts to recover Chozo relics and Artifacts. Somehow, these entities are able to interact with the physical world, and it appears they wish to keep their Artifacts to themselves. We will make them pay for such arrogance, for even ghosts can be destroyed." —Pirate Data "Chozo Ghost" (Metroid Prime)
- "Toxicity levels critical. Contact with contaminated water extremely hazardous." —Scan Data (Metroid Prime)
- "At the highest point of our city lies the fountain, a wellspring of pure water that flows throughout our civilization. It is the jewel of the Chozo, the life-giver, and yet its waters speak of a clouded future. As we come to understand the paths of time and space more clearly, we have begun to glimpse rough tatters of past and future, glittering behind reality like soft lights behind a curtain. We have seen the fountain in these glimpses, pouring darkness instead of water, and we cannot guess what the visions mean." —Chozo Lore "Fountain" - NTSC version (Metroid Prime)
- "This mutant plant is the source of toxic water in the Ruins." —Metroid Prime Logbook "Flaahgra" (Metroid Prime)
- "Vast portions of tree’s cellular structure have been consumed by toxins distributed though source water." —Scan Data (Metroid Prime)
- "Overwhelming toxins have rotted all leaves." —Scan Data (Metroid Prime)
- "Roots originate over walls. No decomposition detected: host plant appears to thrive on toxic water." —Scan data (Metroid Prime)
|Spanish||Ruinas Chozo||Chozo Ruins|
|French||Ruines Chozo||Chozo Ruins|
|German||Ruinen der Chozo||Chozo Ruins|
|Italian||Rovine Chozo||Chozo Ruins|
Rooms in Metroid Prime