Gotta say, you’ve got a point here. I haven’t heard about it, even though I am familiar, at least to some extent, with the folklore (wouldn’t call myself an expert or anything, but still) and can speak the language.
Jokes aside (although you did write some nonsense, mostly re MMR etc, after that, while I was typing my previous post, as if to confirm the point about the brain. 
We’ll get to it later), I suspected it were a reference to some form of ‘schematic’, which is Greek in origin (probably with a ‘ki’, or ‘chi’, i.e. ‘Χ, χ’, there, something like that).
Wait, what? Are you certain you’ve not fallen victim to some hoax or amateurish pseudo-historical or pseudo-lingustic theory?
I mean, I’d understand if you made a reference to a Persian phrase “Shāh Māt!” or something like it, see, for example:
https://en.wikipedia.org/wiki/History_of_chess#Origin
https://en.wikipedia.org/wiki/Checkmate
But usually, when people draw such parallels based on how similar things sound purely by coincidence, it’s a sign of such amateurish theories.
I mean, ‘Fel magic’ sounds like outright ‘wrong (magic)’ in Swedish, for example, but I strongly doubt that’s where the name comes from. 
Anyway, back to the brawl in question…
As said, it has already dominated such events (check out HSTD if you’re interested, like reports about the previous theorycrafting events or brawl), and seems like an obvious candidate that would have dominated this one.
PS Okay, even did some digging, for example:
https://www.hearthstonetopdecks.com/tavern-brawl-the-lost-city-of-ungoro-pre-release-brawl/ (I suppose one could call Paladin quest the new Ursol, or Murloc Pala the new Imbue Pala?),
https://www.hearthstonetopdecks.com/what-to-expect-from-the-lost-city-of-ungoro-theorycrafting-event-impressions .
It’s got nothing to do with any ‘MMR’ nonsense, let alone Standard Ranked play.
It’s just a strong deck in a format without cards from the previous year, and that’s it.
I dunno why you keep going on with this rubbish.
Again and again: it’s not a strong deck in Standard, with many counters and whatnot, but it has been and probably would be* dominant in this kind of format.
* Haven’t play-tested this one, though, but I consider it a reasonable guesstimate; in fact, when they announced the brawl or something long ago, one of my first thoughts was like, what are they gonna do about Quest Paladin this time? It’s such an obvious pick even without any new cards… unless they ban it, which they probably will do.
No, it hasn’t got anything to do with rank, ‘skill’ (I keep maintaining it’s not a significant factor in HS), performance, some alleged ‘MMR’ or whatnot. Not even the Pavelling book would help with that, I think.
Now, that’s actually a curious point: it would be interesting to see how this one fares without the old cards on which the ladder deck relies heavily.
If memory serves, it wasn’t that impressive last time, but the quest was buffed, wasn’t it?
Anyway, that was my next candidate after Murloc Paladin. Maybe we’ll see, maybe they’ll ban it, too.