Chozo Statue

Chozo Statues are statues made by the Chozo and were put on planets to observe their sentient inhabitants. The Chozo Statues often help Samus Aran in her quests by offering upgrades for her Power Suit that help her defeat enemies. The most powerful Chozo Statue was the Chozo Guardian. An aggressive subcategory known as the Torizo resemble the Chozo Statues, but will move around and even attack Samus.

Some statues can be destroyed, but most are impervious to damage. They seem to have limited sentience, possibly containing Chozo Spirits of sorts. This is supported by the Meta Ridley boss battle in Metroid Prime, where the statues surrounding the Cipher retaliate and blast him into an abyss at the battle's conclusion. Some statues' eyes glow bright yellow.

Appearances
In Metroid: Zero Mission, Chozo Statues give health and missile recharges. Some statues will also show Samus the location of other statues that are holding Power-ups.

A Chozo Statue can be seen in Metroid Fusion, but it is actually an X Parasite mimicking one. This implies that Chozo Statues are organic in nature, as the X-Parasites can only mimic biological organisms.

In Super Metroid, some Chozo Statues will help Samus navigate her environment. For example, one in the Wrecked Ship carries Samus past a bed of spikes and into a passageway leading to the Gravity Suit; another found in Lower Norfair will drain the acid out of the room to allow further progression, granting access to the Gold Torizo mini-boss battle and the Screw Attack.

Several appear in Metroid Prime, but the most notable is the large monument statue that gives Samus access to the Ice Beam, a Chozo Artifact, and an Energy Tank in the Hall of the Elders. It is guarded by several Chozo Ghosts.

Two appear in Metroid Prime 3: Corruption, one at the entrance to SkyTown which has been shrouded by Phazon vines, and another that holds the Spider Ball. The statue that holds the Spider Ball is in the typical Chozo Statue position, but it is more Chozo-shaped and appears to be wearing the Varia Suit.

Creation and Function
Scans in Metroid Prime indicate that only select, trained Chozo are permitted to create statuary. The statues themselves (or at least some of them) may have organic properties similar to the Chozo's Power Suits, as the X Parasites were able to mimic one. This further supports the theory that the statues are at least partially alive and aware of their surroundings, though to a far lesser extent than the Elysians. While they are highly decorative and are placed in obvious and central areas, they frequently appear to display functional purposes. The functions of the statues are generally well-concealed to those who the creators did not intend to find them; functions include motion, data storage, healing properties, defensive capabilities, and the common concealed upgrades. This may explain why the Space Pirates have not been able to reliably use or reverse-engineer Chozo technology despite being proxy to it.

Metroid II manual
Artifactor Statue - "This is a relic of an ancient civilization. This statue holds the item sphere."

Super Metroid manual
"The ancient bird people of Zebes are immortalized in the form of several statues scattered throughout the planet. By firing on the balls that are held by many of these Chozo statues, you'll reveal special items."

Metroid: Zero Mission manual
"Chozo Statues often hold items. Change to Morph Ball form on a statue's palm to have all energy, Missiles, and Power Bombs filled to the maximum. "

Super Smash Bros. Melee
In Super Smash Bros. Melee, a Chozo Statue appears as a trophy, which reads:

""These statues, which provide power-ups to Samus and have some connection with her Power Suit, have been found in many places, most notably Zebes. The Chozo boasted the most advanced civilization in their galaxy. Some say that when they could advance no further, they chose to withdraw and observe other life forms."

The Brinstar stage also has a Torizo in its background that stands up and walks around, but has no impact on gameplay.

Super Smash Bros. Brawl
The Brinstar stage from the previous game returns, and it also has a sticker.


 * Chozo Statue Metroid II: Return of Samus-  [Aura] Attack +25  (Lucario)

Trivia

 * One of the statues in Metroid Zero Mission in Norfair is broken and cannot be repaired.
 * In the House M.D. episode "Occam's Razor", House can be seen playing Zero Mission on his GBA SP several times. In two of these scenes, Samus is shown rolling into the hand of the first Chozo Statue in the game, apparently causing a Game Over.