The following is NOT canonized by the TTV. Anything listed serves as potential material for the TTV, if they ever want to use any of it. Anything they reject outright (assuming any of them read this) will be labeled Non-Canon.
This post was originally in my Brickonicle in the Future megathread, but it took too much space in the initial post. Now, it will be here for the sake of space and a better discussion regarding the concept. Keep in mind that none of this is canon. The name of this race is subject to change.
Beings created by the Brothers Ekimu, Karzahni, and Makuta prior to the formation of the world (Mata Nui's Coffin). Telepathic. Adaptive biology, including superior regenerative healing and mutation abilities. Immune to disease, poison, age, and the vacuum of space. Possess near-transcendent intelligence; capable of "manipulating" probability.
Annona: eldest and most powerful of the Three Brothers' creations. The embodiment of destruction, chaos, and secrecy. Possesses an innate connection to darkness and shadow. Able to produce offspring on her own. Sealed within the Sun by Mata Nui.
Morbuzakh: offspring and servant to Annona. Comprised of a black-green swarm of arboreal and tentacle-like appendages. Capable of self-replication through seed pods; possesses hive-mind. Possesses anti-venomous properties within blood. Empowered/healed by heat and fire; damaged/weakened by cold and ice.
Tren Krom: offspring and servant to Annona. Comprised of a red swarm of tentacle appendages. Capable of body-swapping. Creator and original wielder of the Mask of Shadows, using it to shroud himself in darkness, allowing him to generate telekinetic shadows and clones/shadow leeches (and swap places with them), cloud others' vision and mind and drain one's inner light.
Beings created by the Brothers Ekimu, Karzahni, and Makuta to act as guardians and emissaries to the Matoran. Physical superiority to Matoran, with immunity to mind-control (built-in warning to feign complete control near Makuta) and death relating to age, disease, or poison. Transform into stone upon death. Able to wield raw energy. Comparable power to a Toa. Divided into four groups: Ekimites, Karzahnians, Makutans, and Exiles.
During the War of the Brothers, many Kal were slain in battle, both by the Toa and their own kin, until only a few remained.
Ekimites (Hand of Artakha)
Servants of Ekimu. Image by @RAKRONDEWL:
Axonn (The Arbiter): Arbiter and one of the Two Champions. Retains his Mask of Truth (Rode) to properly extract information from the inhabitants. Inspiration for the Artibers' Kritarchy in Naho; revered. Image by @RAKRONDEWL:
Brutaka (The Messenger): Courier and one of the Two Champions. Retains the Mask of Dimensional Gates (Olmak) to travel between worlds. Image by @RAKRONDEWL:
Hydraxon (The Warden): Former ruler of the sea; warden for prison where Karzahni is held. Wields the Mask of Repair (Kiril) to repair damage done to the prison and reinforce it. Amphibious. Immune to heat. Image by @RAKRONDEWL:
Keetongu (The Sage): Sage residing in Tiro. Wields the Mask of Healing to cure the most deadly and unnatural of diseases and poisons. Can sense a being's spiritual alignment. Completely mute, voluntary. Revered in Tiro. Nemesis of Roodaka. Image by @RAKRONDEWL:
Umbra (The Pure|The Guardian): Clandestine guardian and caretaker of Mata Nui's heart, Karda Nui. Wields the Mask of Light (Avohkii) to signify purity of heart. Can sense a being's spiritual alignment. Empowered and aggravated by spiritual darkness within nearby individuals. Immune to energy. Nemesis of Umarak. Images by @RAKRONDEWL:
Servants of Karzahni. Image by @RAKRONDEWL:
Irarok @DarkMaestro (Apotheosis): Aquatic. Telepathic:
Khambrass @AntrozT6 (Barraki, Mahri-Nui- Year 3, 4?): very large (30 m). Highly intelligent. Possesses camouflage:
Servants of Makuta. Image by @RAKRONDEWL:
Irnakk (The Nightmare) (diffused): Warrior. Original wielder of the Mask of Fusion to forcibly fuse multiple beings into a single entity or divide them into multiple entities; effects can be forcibly undone via removal of the mask. Original wielder of the Spear of Fission to willingly undo all fusions/divisions, or to forcibly divide individuals. Driven insane by Karzahni, causing self-fission. Currently diffused into seven beings, which all inherit his powers:
Avak: Rebellious. Possesses enhanced vision. Highly skilled engineer; well-respected in Motara.
Hakann: Cruel and unpredictable. Immune to fire and heat. Telepathic.
Reidak: Cunning and highly intelligent. Strength and endurance superior to a Toa. Highly skilled hunter. Able to track heat signatures and possesses night vision. Combat-adaptive biology.
Thok: Cunning, manipulative, and solitary. Higher core temperature to adapt to cold.
Vezok: Highly aggressive and paranoid. Extremely agile. Adaptive biology.
Zaktan: Cruel, cunning, and enigmatic. Commander of Makuta's forces.
Kulta (The Skull Grinder|The Lord of the Skulls) (idea by @Toa_Vladin, edited): Zealot. Only Kal without free will. Skeletal in appearance. Sadistic by nature. Wields the Mask of Reanimation (Tryna) to summon the corpses of the slain to fight for him. Rival of Umarak.
Roodaka (The Viceroy): Sidorak's wife. Wears the Mask of Mutation to manipulate the physiology of beings to her will. Nemesis of Keetongu.
Sidorak (The Rahi Master): Former Ekimite Rahi Master and friend of Keetongu. Wears the Mask of Rahi Control, gifted to him by Makuta out of mutual respect. Able to communicate with and tame Rahi with resistance or immunity to mind control.
Umarak (The Shadowed One|The Hunter|The Destroyer) (idea by @RAKRONDEWL): Leader of the Dark Hunters. Able to generate powerful barriers from raw energy. Current owner of the Mask of Shadows, used to shroud himself in darkness, allowing him to generate telekinetic shadows and clones/shadow leeches (and swap places with them), cloud others' vision and mind and drain one's inner light. Rival of Kulta. Nemesis of Umbra.
Vezon: Formerly Irnakk. Rebellious, insane, nihilistic, paranoid, and possessive. Brilliant tactician. Wields the Mask of Fusion and Spear of Fission.
Maxilos: Created by Ekimu, with Hydraxon's influence, to serve as guardian robots for the island; now guard Karzahni's Prison. The same build as Brutaka. Capable of boiling water within their immediate environment to ward off intruders. Immune to heat. Aquatic.