Viy probably needs to be nerfed. Adding several provisions or nerfing the power per usage would be nice - or both.
While I was able to beat Viy with ST movement, I had to spec Yrden to do it. With Malena, Viy is manageable but I still can lose from a 2-0. But this isn't the main problem.
Viy invalidates a huge amount of decks and potential decks that could appear with the new expansion. Let's look at the top decks from last season.
SK warrior - no chance to beat Viy really, Mork is the only counter. Hjalmar used to be a great removal card, now it's useless.
ST nature's gift - imagine getting a 20+ point dryad, that'd be great right? Now imagine you have 4+ of those with little counter play. That's Viy.
Shieldwall - Wow, Anseis for 20 points! Huge! lol
I think you get the idea. Last season decks can't deal with this. But we're tired of those anyway, right?
SK in its current form, whatever that is, has no chance, so we can rule out SK. NR can hit the high points, but only if it isn't bled and wins round 1, which is very difficult versus Viy, so that probably won't work either.
NG seems like it should be the natural counter, but actually, because of Viy's provision being less than oneiromancy and haunt, you aren't able to disrupt Viy. ST as I said earlier, has the best shot I think, but one deck from one faction probably means we have an issue with balance.
On the other hand, we can all just run syanna + salamander, right? Problem is that's a... 4 card combo? Salamander, roland, rayla, syanna. Viy on the other hand... i've never seen it NOT pop off.
Even the counters, besides Yrden seem strange. Spores comes to mind, but if you think about it, you actually don't gain much. So let's say they play barghest and consume a 20 point Viy. You play spores, great, you got a 15 point spores. Unfortunately, they got a 20 point barghest and you have a 5 point deficit regardless.
These counters have other side effects too. In order to counter Viy, you need neutral cards like spores or Yrden in most cases. This means that devotion decks can't really be played. Maybe Viy should be made a devotion card itself?
So we can say that Viy invalidates many decks, making for a potentially stale meta. It forces deck builders into awkward corners where they must play certain cards, like spores or Yrden.
While it is fun to see a potentially new archetype, it shouldn't come at the cost of so many existing archetypes becoming invalid in ranked. I think the developers intended for some decks to become viable, such as spies and assimilate, but assimilate doesn't generate enough points fast enough to survive rounds one and two while still allowing for its long round three.