"Pure" decks. Are they viable?

[Upoo]

Since the beginning of my journey in the BF, I wonder about this.
Are single color decks viable?
Currently I'm using a deck that is practically (nature), only with 3 exceptions (magma hurler), and two other constructions (I do not remember names, both stonekin).

My question is, are unique color decks viable?
My focus is purely PVE, complete the entire campaing (in all difficulties) and later random maps in difficulties greater than 6.

Another issue I raise is ... decks containing a pure color, would they be cheap? Or ... would they have their highest value because of the use of only one color?

[LEBOVIN]

For the purpose of just beating the map somehow, sure. But usually customised mixed decks for each map score better in terms of speed and turn out to be easier aswell.

Regarding the price, to achieve same efficency (to an extend if possible at all)  a mixed deck should Turn out cheaper, especially as it is roughly the same cards that are the core of mixed decks for many maps. 

Edited July 22, 2019 by LEBOVIN

[Loriens]

Id like to play Pure Fire deck on expert maps, it's very fun.
If you are not speedrunning these decks are definitely viable.

[Cocofang]

I'd say you play mono decks for flavor. Because you enjoy it and not because it's good.

I don't think there is literally ANY mono deck that couldn't be improved by changing one or two orbs. The T4 mono cards are all pretty underwhelming for how restrictive they are. Green Forest Elder is nice. But Nature itself is such a good allrounder and can get away with playing it mono. Dreadnought is powerful but clunky to use. Shadow Worm is pretty useless without support to sustain it. Moloch is slow and therefore worthless. Batariel is strong but also works best with support.

Meanwhile just slapping one nature orb into any deck gives you amazing T4 with Grimvine and Giant Wyrm. And insane support spells like Regrowth, Revenge and Equilibrium. Give me those any day over any mono T4 cards.

You can probably beat any campaign PvE map with a mono deck. But I wouldn't expect to ever be as efficient, fast or successful as a mixed one.

As an added drawback your concerns regarding the price are probably justified. You always have to consider that the market value is extremely volatile with how small the community will be. The prices for certain cards can be easily manipulated, the market can be cornered and the lack of supply can just generally have all kinds of wacky effects. With that being said, judging from the AH prices during this stress test the mono T3 and T4 cards were mostly pretty expensive. Avatar of Frost, Juggernaut, Spitfire and Abyssal Warden are the mono T3 cards that end up being on the more expensive side. Satanael is mid range. Northland Drake is cheap because it is so common. Mono T4 is expensive with Dreadnought, Shadow Worm and Forest Elder. Batariel is dependent on the affinity. Either low or mid range. Moloch is somewhat cheaper. That's all just from memory.

Of course that assumes that you really want to fully commit to mono and not only actually need 3 orbs of the same color but leave your deck mono anyways.