Arcane Discover Mage

Overview - Place in the Meta and Hero Power

Mage has 3 main spell schools they can build around in duels. As of now, Arcane Mage seems like the least explored one, with frost and fire builds having an easier time revolving around either control/value (Frost) or burn damage(Fire).

At the moment of writing, I have only concluded two run with this archetype in particular (7 and 10 wins) I hope you can still appreciate the insight based on my general love for control mage lists and experiences with the current duels meta (7900 MMR)

As it turns out, Arcane Mage falls somewhere between the two. Devolving Missiles is a strong tool to deal with board focused decks like Deathrattle Hunter, Divine Paladin and some Token Druid openings. In addition, Infinite Arcane Combined with the versatility of the different discover effects help you prepare for any kind of lategame. If that's not enough, Stacking multiple buffs of Aegwynn, the Guardian will ensure you will gain the upper hand as time goes on. Don't be fooled, she is no budget Mozaki!

On the other hand, the deck has the potential to be drafted towards a more tempo oriented build. Wyrm Bolt is a meta pick. Currently, most Mages play Frost Shards, which Wyrmbolt counters quite well. The other decks mentioned above also struggle to clear the Mana Wyrms efficiently, allowing you to finish games early with the many spell the deck can chain in a turn. Also look out for cards like Unexpected Results in the spell damage based buckets and swing the board with cheap board clears like Shooting Star. Be warned though, dealing with minions is an integral part of the starting list, meaning that unless your priest opponent is playing dragons, there won't be much tempo to be gained without the help of a passive later on.

Card by Card - List explained in detail

It feels bad to build a deck around a single Passive Treasure only to miss the mark and have subpar results. It's the reason I usually go for more consistent strategies. The list was created with the main idea to make the Arcane passives work, thus we avoid spells of any other spell school and run a minimum of "neutral" spells, like Ring Toss if you can call them that. The plan B and C strategy is to include as many spell damage and discover synergies as possible. If the reason doesn't seem apparent, look at the Passive Treasures Tierlist at the end of the guide for more detail.

• General good Arcane Spells
  
  As the Baseline of the deck we have Devolving Missiles, Primordial Glyph and Runed Orb. I already went into why Devolving is a good meta call depending on the match-ups. But the discover spells are just as important. They make sure your Mana Wyrms are capable of high burst turns while also giving you the versatility for any situation.
  
  
• Why Arcane Spells + Spell Damage synergizes
  
  At first I was looking into Arcane Spells working well with Secrets, Counterspell is a strong weapon against Spell based decks like Priest, which we struggle the most against. I still think so, which is why I ended up with Ring Toss as one of the last additions to the deck, filling the aforementioned gap while also doing it's job as another discover effect.
  Notable Arcane Spells that incorporating a different synergy are Primordial Studies, Cram Session and arguably Arcane Missiles with Shooting Star.
  Studies is a real multitalent that represents all 3 themes of the deck in a single cheap spell, the backbone of the deck.
  Cram Session is there as a safety. If all goes well, you'll generate so many cards that your happy to get this out of your for just 1 draw. What if you whiff on those S Tier Passives though? Cram Session can refuel your hand while you build you commit to your board, perfect for a tempo oriented aggression.
  Missiles and Shooting Star are your pay off for stacking Spell Damage. it's vital that these are this cheap, allowing you to deal with the early-game threats, so you can later discover more answers for the late-game, tailored for the match-up.
  
  
• Discover Minions, always a safe bet
  
  I first noticed the trend of neutral discover Minions in the successful Deathrattle Discover Hunter. It shows that the meta is slow enough to include Pandaren Importer and Venomous Scorpid. To finish up, Mage has unique discovers in Wand Thief, Primordial Glyph and Runed Orb. This rounds out the package nicely while not clashing with any of the established themes. Regardless of their own merits, some minion need to be added to the deck to enable the secret weapon of the deck, which we'll come to now...
  
  
• Legendary Finishers
  
  We have a few Legendaries to choose from. Though I went with Aegwynn, the Guardian and Ras Frostwhisper, theoretically Mozaki, Master Duelist and Keywarden Ivory fit the bill of the deck as well. However, Ivory is too slow in practice and her payoff isn't too great all things considered. Mozaki is a different case. Early in the run she could be argued to be better than Aegwynn, put in a Conjure Mana Biscuit and discover more cheap spell to end the game with a combo. Turns out as the deck size increases this combo playstyle falls off heavily. You end up with a 5 Mana 3/8 and a random cookie not accomplishing much on their own. Aegwynn can be seen as the opposite to that. She is viable in this build since we run a good amount of minions to keep the inheritance effect going. But instead of building up massive spell damage in a single turn, we use discoverable copy effects such as Potion of Illusion, Molten Reflection and even the Arcane Active Treasure Ancient Reflections. From 2 to 4, 4 to 8, 8 to 16 and so on you quickly build up the necessary damage to finish any stall heavy game. It's important to note that without Infinite Arcane such a longtime gameplan would not be feasible.     
• Odd ends
  
  In the end there are still spots left for flexible additions. I experimented with Steward of Scrolls and Conjure Mana Biscuit but found them to be a bit to slow. Currently my choice landed on Leyline Manipulator and Ring Toss. The Manipulator is Arcane Luminary's big brother. Unlike lil' bro, his effect can be used without having to take advantage of it on the spot. In addition, many Passives share the "but not less than 1" restriction, which is great to overcome for more explosive turns.
  I already went over my preference for Ring Toss, but it can be said that with it's high cost are other cards you'd be happier to see in the first rounds of a run. Don't blame me if you don't have a Flame Ward up to stop the second wave of LOCUUUUSTS!!! from killing you though.

Passive Treasures

Like any other Duels Deck, the passives matter the most in deciding all following choices, including Mulligan, Card choices and defining a win-condition. Below I have visualized the Passive Treasures based on their merit for the deck in general. Do note that within each tier, the left-most is considered best. Passives that have nothing to do with the deck have been omitted since 3 at once probably wouldn't show up anyways.
A rule of thumb to keep in mind though, is that normally a versatile deck, such as this, in a diverse meta will need to strike a balance between value and tempo, which is why the ratings for the Passive of the 2nd pool shouldn't be taken at face value. For example: Emerald Goggles. It's effectiveness can  be based on whether your first passive was also tempo oriented, like Sticky Fingers or value, like Arcane Flux and Open the Doorways. 

https://tiermaker.com/list/hearthstone/hsduels-1st-pool-passives-27-10-21-1319572/1729312

https://tiermaker.com/list/hearthstone/hsduels-2nd-pool-passives-27-10-21-1319572/1729309