What Exactly are Illaoi's Powers, and which champions would survive the test of Nagakabouros?

The Kraken Priestess is the prophet of the Great Kraken and the Truth Bearer of Nagakabouros. According to the her lore, her powers are as follows:

> As the prophet of the Great Kraken, she uses a huge, golden idol to rip her foes’ spirits from their bodies and shatter their perception of reality. All who challenge the “Truth Bearer of Nagakabouros” soon discover Illaoi never battles alone - the god of the Serpent Isles fights by her side.

But what exactly does this mean, and how would her abilities be expressed in the context of a fight? I've read Shadow & Fortune and instead of engaging in combat with the champions of the Shadow Isles she channeled the energies of Nagakabouros to drive back the fog and stop the harrowing, but what would have happened if she was forced into a battle with Hecarim or Thresh? If her powers are innate, it suggest she's the living embodiment or the direct vessel of a god(or LoL's most powerful lore character to date), and if that's the case I'm curious how she stacks up against the Ascended, the Aspects, Aatrox, Tahm Kench, Mordekaiser, Braum, and some of the LoL universe's more powerful champions given rioters descriptions of her powers:

{quoted}

+1. It is rare, but it is only a "tool." Like a hammer or saw. It would be replaced. The power comes from her connection to Nagakabouros, the Eye of God just helps her focus.

and

{quoted}

He would avoid her.

Ha. As much as I loved writing Tahm taunts -- because of production schedules probably won't see this for a while.

Finally, which champions would survive the test of Nagakaborous?