Hylla

Hylla, in a way, is a strange form of ghost - though I don't think that Hylla should have anything to do with it. Hylla is a derivation of god-ghost from an ancient lost tongue and while it technically applies only to the post-mortem form, it is used pretty much for all uses. In technicality, the mortal form is referred to as Vanna. Of course, no one has been able to discern the exist purpose and origins of Hylla but it is highly suggestive of an intelligent greater being. People have drawn links to God's involvement in the teleological occult and the Thallassic Annihilation, two of the more promising arguments for His divine existence for those who are aware. The Cult of Hylla is undertaking research into God and His nature and the purpose behind Hylla.

Most parties agree not to let any information slip as it will cause mass panic and social breakdown. These include the Cult, Ualek and several private interested individuals. And also apparently Hylla itself - it seems that the absorbed mindset acquired on ascension favours secrecy and containment.

Hylla is not able to bestow lesser powers whilst they are in their mortal form.

Of course, due to the extended lifestyle, Hylla typically goes for the more interesting people and mostly watch to see if anything exciting happens (can they turn off or ignore their half-omniscience?) and perhaps even interferes with their lives. The typical selection procedure for the subsequent generation is mostly endowing onto those who are interesting or are likely to do something interesting with their greater abilities. Fortunately, they tend to be quite reasonable and responsible in the god-ghost form at least, so don't do anything overly showy to avoid gathering attention.

Korra - end of the world. Voice of all humanity speaking. Constantly shifting features, piercing white eyes.

Perhaps the voice of Hylla can swap between an amalgam of all humanity's speaking in perfect unison and the host's voice.

Can teleport (background changes around them, cinematography) and can interact with one person while still being invisible and intangible to everyone else.

Explain the automatic benevolence reflex.

There was a dude who could summon millions upon millions of voracious neurotoxic ants (native to Milynv) and instantly and gruesomely destroy entire armies. This whole thing needs more work.

Latency issues power

Psychic retreat

Nyjo Fiejihkhip was a cultural heiress who was one of the last members of a dying cultural group, probably Western and due to globalisation and cultural invasion. Therefore, in order to preserve and showcase the culture (perhaps giving it more influence), she went on a voyage to Carroway for the world fair. However, in her plight, Hylla granted her a supernatural power which is pretty much Far Reach, partially to see what would happen. Turns out she was confronted in an alley and tore her aggressor's head off. I suppose there is no build up time for a hyllic power in terms of adeptness. Eventually was spotted by a Nodepok scout and became an assassin, who promptly forgot the cultural quest. Threatened by Hylla not to throw the whole thing into the limelight.

When one gains an occult ability through exposure or whatever, they go into a trance. I imagine it as being something like exploding dyes, mixing and marbling. One sees the orkar wheel responsible for such ability though memory quickly fades. Thus, in the interest of furthering knowledge of orkar script, the Cult typically interviews the people to see if they can gain any new glyphs or anything.

Khoa Ode'mod
Throughout her Hylla timespan, Khoa has befriended a fair amount of people and some of whom she has given knowledge or even aided in their various quests. To an even smaller, ever more significant few, she has gone so far as to grant them brief and inconsequential supernatural powers. Khoa Ode'mod (Ode'mod is the tribe, originally so small that no distinguishment was needed) wasn't in life intelligent enough to create a powerful centralised state rivalling those of Aowa, just to create a short-lived and brutal empire over dozens of tribes in a section of Hatag. Open courtroom, with a platform high in the trees to which she could levitate herself and others up to. After her death, she portrayed herself in her tribal empress dress with an afro (lending to the Black Halo name). Had mild telepathic powers. Only ever person to discover her soulmate, hence her choice as being interesting.