@Fedrion: The stats are a little odd, having aggressive stats but a defensive ability. I would make it a 3 mana 2/3 or something like that. 4 mana feels like a lot and I don't imagine you would be able to combo this with more than 1-2 spells. Also, what happens when you play a frost spell that freezes on a non frozen minion. Does the Cryomancer add a damage? Or do nothing?

@Nirast: Natural Evolution seems a bit odd flavor-wise and problematic balance-wise. The Frost King wouldn't be enough for freeze shaman, and it seems a bit random that he affects fire spells. Out of all of the mistresses I would go with Ice and Fire.

@BloodMefist: I prefer Vile Instructor. The design feels better both in terms of playability and flavor. I would consider reducing the health to 4, but other that I like it as it is.

@Linkblade: These both seem rather over powered. Getting a 6 mana Ragnaros is very powerful, especially when it comes with an extra 2/4. And casting 8 fire spells should be fairly easy in a dedicated deck. Compared to Jana'alai, this costs less, and it easier to trigger, and isn't legendary. I would increase both the cost of the card and the number of spells required.

Fedrion - I feel like this card is quite underpowered, similar in power level to Demented Frostcaller as a whole but working only with frost spells.  Also, aren't frost spells supposed to freeze anyway, so the first part isn't going to affect anything?  I would lean into the second part more, something like "After you cast a Frost spell, deal 3 damage to all Frozen minions." to make the effect more clean rules wise.  I echo KANSAS's concern about the stat distribution.

Nirast - I like the idea of multiple evolves in one turn, but Natural Evolution is clunky in my opinion.  You need a board to set up, multiple nature spells in hand, and at least 5-6 mana when you could have played Desert Hare and Evolve.  Also, Natural Evolution sounds more like a druid card.

Frost King Malakk seems weird to me. Shaman isn't a main fire spell class and the card wants you to freeze your own minions with nature spells, but nature spells will likely kill your minions before they can be buffed.

Of the Mistresses, I like the one on the right the best, because it fits the best with the classes that want to run it.

BloodMefist - I like Vile Instructor a lot.  I would consider having it summon one minion with those stats instead of having it spread wide, but I like it as is. Cruel Inquistor is a little weird because spells don't have attack, unless you mean if it summons a minion with that attack. Also, we don't have that many fel spells yet, so subdividing a spell type seems pretty narrow.

linkblade91 - I feel like Herald of Flame is too dependent on your opponent having enough targets for your fire spells for it to reliably activate.  With Jan'alai, you could activate the hero power each turn or set up an odd mage build.  I like Herald of Light a lot more becuase you can more easily build around it and we don't have a card that generates this version of Ragnaros.

Swizard - Hard to evalutate the first card, power wise.  I think the effect is really cool, reminds me of a Tess Greymane a bit, but I could see this being a super Pyroblast.  I rather not have this target only minions, as it makes it reads more like Reno the Relicologist and that card looked underwhelming at first glance. I would try to think of some other payoff for casting all those spells besides recasting them for balance reasons.

I think the second card is also interesting, but dividing spell types by cost seems kind of narrow.  I think this version is better than adding the spells to your hand, because Nirast has very similar cards in the mistresses.

Natural Evolution – really hard to judge, but great concept. I guess it’s hard to pull off to have a lot of spells and a lot of minions, but this would work great with Instructor Fireheart. Only the nature part in the title is kind of overkill. 

Frost King Malakk- honestly the first part is somewhat bland, and I don’t really like that there are two different effects here. Kinda meh, you know?

All the Mistresses: nice, simple, great find for the art. Although individual names would probably make those feel more legendary.

Vile Instructor is a great design, seems mostly fair – except for Hand of Gul’dan, as you pointed out – and could be a great agro tool in token demon decks.  Maybe just a -1 in stats to make it fairer, without being unplayable.

Cruel Inquisitor: Also good. Great name for the effect, seems fair!

The art doesn’t fit at all, you’re right to change that. And might be a bit of a longshot, but could you make them neutral? Maybe shaman or druid get a few fire spells, and a dedicated deck could use a pair of those as a finisher.  Herald of Light is also great, would be greater as a neutral card. And KANSAS  is right for the Herald of Flame: the cost is too low, for the Herald of Light the cost seems fine.

Ilxos is flavorful, but isn’t Ragnaros the Flamelord? And ‘targets enemies if possible is possible’ is too much in my opinion. Looking at all possible Fire spells from mage, there are only five that can damage your hero: Firelands Portal, Pyroplast, Dragon’s Breath, Fireball and Flame Geyser. And mage is an RNG focused class, so a near sure one-turn win card is somewhat misplaced. After a careful game of clearing boards and large minions, you can play this one card, even if your opponent has 29 more health, and you could win the game. I think this wouldn’t be fun.

Arrogant Gnome: Unstable Gnome is better. The card is way too strong for its cost, it has typical 5mana stats but with a hefty upside. But I like it flavorwise, but I feel it should be rare.

Abundance: What a lovely and simple card. Feels druid-y, fair and can be a great survival tool. Only small caveat – while I’m a sucker for Tauren, the card looks more like a healing card and less like an armor-gain card to me. Maybe find the tauren druid from the expansion trailer for the pic.

Kor’Kron Immolator: Another beautiful and simple card. Seems very good for its cost, especially since you can slap it down turn 10 with Flamestrike, but then again you’ll almost never get more than one or two cards from this.

I think your card needs a major overhaul. A cheap minion, with okay stats that can buff several minions a substantial buff? That’s way too much for one mana! Just look at this + Imp Swarm (Any Rank) : 3 mana, and you get a 1/2 and up to three 5/4 demons! The effect is just too powerful for the cost, since Warlocks have a history of summoning small demons with spells, and this card would make all those spells unbalanced. Also it’s quite a simple effect, either make the rarity common or rare, or legendary, so that you can only include one copy.  Art doesn’t look like a hearthstone card

@grumpymonk: I prefer Abundance. Partly because I just really like Druid, drawing cards, and gaining armor. But also because I have a feeling that a lot of people are going to be making Fire spells, so staying away from that school may help your card stand out more. I do think Abundance is a little powerful as it is. It shouldn't be hard to put only nature spells in your deck, so this can easily tutor 2 spells and gain you a hefty amount of armor. Maybe if it only drew one nature spell and gave you armor for the cost, or if it gave you 5 armor instead of armor equal to the cost.

@Dreams: First off you shouldn't use the Classic watermark. I think this card is very powerful, I would either increase the cost or make it buff +1/+1 instead.

@Neoguli: This basically gives your arcane spells a soft version of twinspell. I think it is an interesting idea but in practice I don't see this surviving more than 1 turn, which means you probably won't be able to get more than 1-2 spells from it. I would make it cheaper and smaller, and just have it buff a random arcane spell in your hand with twinspell, or have it generate a copy of a random arcane spell in your hand. This would make the design much cleaner while keeping the card roughly the same.

@NerdyMcNerd: I don't have anything to criticize. The card looks great! :)

@KingMicahhh: First off you shouldn't use the Classic watermark. My main concern is that it is too similar to Lyra the Sunshard. It has the exact same cost/stats and has a very similar effect. You did a good job on flavor, but I would adjust it slightly to make it a bit more unique.

@anchorm4n: I like it but I agree with other people that this could very easily become problematic. I would make it a 7/7 and have it affect only the first spell.

@Elfensilver: There is a typo in the word "whenever" and it should also say "your hero" instead of "you" in the battlecry. I like the design but I would change the battlecry to a "when drawn" effect so that the opponent can't just hold onto it and avoid taking damage.

melsterz39: It's a pretty interesting idea, but limited by whether your opponent is playing a Nature class (which at this point is Druid/Shaman and maybe Rogue?). I think you can drop the Mana cost down to 1/2 and not have it be oppressive.

KANSAS: I like it, but definitely change the art (you could probably put it in Barrens if you can find a good Totem).

Elfensilver: You could switch from Whenever to After and then have enough room to switch 'you' to 'your hero' within 4 lines and make it more consistent.

anchorm4n: I really like Kael'thas, good effect and flavor.

Neoguli: There's interesting applications for this, but it seems very complicated and locking out your hero power with Arcane secrets just means you have less Arcane spells you can play or less hero powers which isn't a good idea for a card that is supposed to support both deck types.

grumpymonk: Abundance needs to cost at least 4/5, it's way too good at this point. Kor'kron is at a good balance right now and fits the flavor of Fire Mage.

Swizard: Ilxos is a good finisher, but I don't know how a combo card will do in the voting stage. And for Arrogant Gnome, I'd go with the adding random spells variation instead.

linkblade91: I prefer Herald of Light out of the two, it has less ways to abuse it than Flame and avoids the comparisons to Jan'alai that Flame would inevitably get.

BloodMefist: I prefer Vile Instructor out of the two.

Nirast: I like Natural Evolution, but if you go with Malakk I'd limit it to just Nature spells since I don't know which Fire spells you'd actually want to cast on your own minions to get the +2/+2 buff.

Fedrion: Simple but effective, I like it (but change '1 addional damage' to '+1 damage')

Demonxz95: Another simple but effective one.

Demonxz95 - I think the first version is more exciting, but this one could yield a more consistent score.  I like both versions equally.

ChickyChick - I like it a lot!  Could enable a lot of mana cheating if there are any high-cost arcane spells, but I don't see that as a consistent enough issue to change the stats around or anything like that.

Hordaki - I like the idea a lot. Unfortunately, 3 mana 1/1s that don't affect the board and require other cards to get going are unplayable in this day and age. I would make it a 3/3. Also, I would consider changing the watermark. As far as I know, there aren't many humans in the barrens.

meisterz39 - To be honest, I'm a little weary of tech cards that can go only in a single class. In this case, if nature spells go out of hand, it could lead to a lot of Shaman mirror matches as other classes don't have access to nature spells or this card.  It's also not fun to play against.  I would rather have it increase the cost of spells rather than countering them outright.

KANSAS - I like it, but does adding a random nature spell to your hand that much worse than a lackey that the totem needed an extra point of health and a 1 mana discount?

Does this work for art? I'm not sure if its what you're going for but it seems more nature focused than other totems.

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Elfensilver - The essence of this card is that it shuffles copies of itself into your opponent's deck, so maybe the battlecry can be taken out? I don't have a good way of cutting down on the text otherwise, sorry.

anchorm4n - I had a very similar idea floating around in my head at one point as a 4 mana 4/5 - shows what I know about balance xD.  The shadow spells we have don't lend themselves to combos - mostly just removal.  

Neoguli - Very interesting.  It does read more like an epic than a rare. Turning your hero power into a spell is very weird, but I guess that's the point.

Dryad of Duskwood II- I really liked the first version with choose one better, even though I found one option to strong.

ChickyChick - It feels a bit too similar to Kanrethad's effect to me. I like the concept in the ogre better.

KANSAS - I like this new design, it could probably reduce the cost by 2 as it currently is (maybe as a 0/2 then just in case). Some crazy boards could happen with totemic reflections that would be fun.

Dreams - I think merlin is far too oppressive with frost spells, and too situational with fire spells. The Armorsmith is interesting, though a bit out of flavour for mage, a no-spell mage could be a difficult archetype to get working, but this is a nice payoff for that - 10 armor might be a touch too high, I'd suggest 8 armor - like an ice barrier.

Merlin,Master of the Elements – I quite like this card, it would work in most control decks.

Magicless Armorsmith . Interesting design, but mage without spells seems impossible.

Searing Summoner: looks strong, but with the quite limited amount of Fire Spells I think it may be fair or even weak if you make this to be a Barren card, since Mage has all of 3 fire spells right now, maybe 4 of Apexis Blast is of the fire school. So while the card is great, I’d maybe change the watermark.

Lurking Shade and Light and Might only add one spell to your hand, whether that is synergizing is a matter of interpretation.  I’d say it’s not, so I would dock a point.

Cycle of Nature looks great, visually pleasing, but hard to judge strength wise. There are 3 zero cost spells for Druid (5 with Ironbark and Bogbeam), and 5 one-cost spells. So there is a lot of cycling possible, especially with the Eclipse Spells, Nature Studies and Lightning Bloom. So with those cheap mana refills, you could find Arbor Up extremely fast, thereby discounting Umbral Owl to 0-Mana, and setting up a Yogg. It’s quite a good card, but in the current meta it could be to dangerous.

Also, and more importantly, Ice spells do not exist. They are called Frost spells.

Also, its new name is Totem Totem, which I believe is not intentional :_D

All in all, I'd try a different idea.

Hellscape doesn't qualify for this comp, unfortunately.

Magicless Armorsmith is also fine, but I'd try finding an artwork which fits Mage a little more.