Krana

"Beware the krana! When worn, they can steal the mind... and not even a Toa might be able to resist their power."

- Turaga Vakama, Comic 4: The Bohrok Awake

Krana were a type of organic species which acted as the brain of a Bohrok and gave it its power. The Krana, besides controlling the Bohrok, provided the intelligence to the swarms.

History
The Krana were created and telepathically guided by Cahdok and Gahdok, the twin queens of the Bohrok swarms. If the queens were either not awake or had their connection severed, the Krana, and therefore the Bohrok extensively, would not be able to operate to their fullest performance.

The Krana, while the Bohrok's power, was also its weakness: even the strongest Bohrok, without its Krana, became little more than an empty shell, which could then be programmed or trained to repair the damage it inflicted. One of the main functions of the Bohrok Va scouts was to replace a Bohrok's missing Krana. If one felt threatened, it could eject from its Bohrok host; this left the host powerless, but if the Krana attached onto another being's face, it took control of that being's mind and assimilated it into the swarm.

The Toa Mata collected 48 Krana, 8 for each Bohrok breed, and placed them into special slots in the middle of the Bohrok nest. This unlocked the hiding places of six sets of Exo-Toa armor and the lair of the two dreadful Bahrag twins. When the Bahrag were defeated, the Bohrok shut down and the Matoran collected, pitted and sealed all their Krana away.

The Toa Nuva were later sent on a mission by Order of Mata Nui member Axonn to free the Bahrag, so they could release the Bohrok and cleanse Mata Nui into a barren state.

Types
There were eight different types of Krana. Each one granted their wearer a unique power and assigned them a rank in the Bohrok swarm:


 * Xa: Swarm Commander--Strategy. This krana led the Bohrok on their mission. Krana Xa command a swarm, giving their Bohrok the ability to form complex plans in order to complete their mission.
 * Za: Squad Leader--Telepathy. This krana gave their host the ability to communicate telepathically with other krana of the swarm. This type of krana controlled Lewa and Turaga Matau for a period of time.
 * Vu: Surveyor--Flight. This krana gave their host the ability to fly short distances ahead of the swarm to confirm that the path is clear, avoid obstacles, or escape a threat.
 * Ca: Clearance--Shielding. This krana gave their host the ability to generate a powerful shield for themselves and others; this type of krana spearheaded the swarm's mission.
 * Yo: Mole--Tunneling. This krana gave their host the ability to tunnel through almost anything on Mata Nui.
 * Ja: Scout--Radar. This krana gave their host radar-like senses which could detect distant obstacles in the path of the swarm. They can help make a swarm aware of possible danger or a hold-up.
 * Su: Worker--Strength. This krana gave their host colossal energy and inhabited the strongest of Bohrok. They were always around whenever brute force was needed.
 * Bo: Sentinel--Infrared. This krana gave their host the ability to see in the dark and serve as night-time lookouts, leading their Bohrok into the darkest places on Mata Nui.

Colors
Each breed of Bohrok wore a different colored Krana. The Bohrok's Krana color corresponded with their eye color:
 * Blue: Tahnok
 * Orange: Gahlok
 * Red: Lehvak
 * Green: Pahrak
 * Yellow-Green: Nuhvok
 * Light Blue: Kohrak

Dormant
The colors of the Krana, while dormant and carried by a Bohrok Va, were different:
 * Yellow: Tahnok Va
 * Purple: Gahlok Va
 * Dark Grey: Lehvak Va
 * Tan: Pahrak Va
 * Black: Nuhvok Va
 * White: Kohrak Va

Set Information

 * A Krana was packaged at random with every Bohrok set; the probability of the Krana being a Xa, for example, was 1 of 8 for each Bohrok breed.

Trivia

 * The "Fohrok", unlike Bohrok, were not controlled by Krana.
 * The Krana would work just as well as a Kanohi on a Matoran's face to keep them awake and alive; however, it also meant that the Krana would be able to assimilate the Matoran into the swarm if the Bahrag awoke.
 * In the Metru Nui Archives, Toa Metru Whenua once nearly knocked over an exhibit of Krana.

Appearances

 * Comic 4: The Bohrok Awake - First appearance
 * Comic 5: To Trap a Tahnok
 * Comic 6: Into the Nest
 * Comic 7: What Lurks Below
 * Bohrok Online Animations
 * Bohrok (Mini-comic)
 * Secret of the Swarm
 * Into the Nest (Mini-comic)
 * BIONICLE Chronicles 2: Beware the Bohrok
 * BIONICLE Chronicles 3: Makuta's Revenge - Mentioned only
 * BIONICLE Chronicles 4: Tales of the Masks - Mentioned only
 * The Official Guide to BIONICLE
 * BIONICLE Adventures 1: Mystery of Metru Nui - In flashback
 * ''BIONICLE: Metru Nui - City of Legends Comic 1 - In flashback
 * BIONICLE: Metru Nui - City of Legends - Mentioned only
 * BIONICLE: Rahi Beasts - Mentioned only
 * BIONICLE: Encyclopedia
 * BIONICLE: Encyclopedia Updated
 * Comic 12.5 - Mentioned only
 * BIONICLE Legends 10: Swamp of Secrets - Mentioned only