For Magic Mirror, the fastest strat is probably to play Majordomo in turn 9 and finish him off next turn with Fireball + another burst card. Stalling is probably easy with cards like explosive sheep, tentacle of n'zoth and doomsayer. (Though I haven't actually played this heroic level yet)

For Big Bad Wolf, maybe Evolve and Wailing Soul can be really strong in transforming all 1/1s into big minions?

There still a lot of the heroics that I haven't tried yet in this adventure, but the 'easiness' of some of the levels means that there could be a lot of alternative strats available for those bosses.

Been playing around with magic mirror and I've come up with 2 possible deck styles, although not fully refined yet (still needs a LOT of work)

Mage - Control board until majordomo and burst damage down Ragnaros.

Shaman - Control board and use ancestors call to get out Majordomo early and burst with spells.

Decklists (not refined) : http://imgur.com/a/uMh4Z

http://imgur.com/a/Tt4Cr

Nightbane:

I have found a consistent deck for Heroic Nightbane that works pretty well. Its a jade druid deck with a couple more bits of removal and some other spells. By using Jade Idols and Gagetzan Auctioneer you can cycle the Jade Idols, minions and other spells to create a lot of large Jade Golems. Cards like Jade Behemoth and Aya Blackpaw are also good for summoning extra golems and helping remove minions. The deck might be more optimised if i had more cards but it'll do for now.

http://imgur.com/a/qXwkh

Curator:

Use spells to control his minions and attack him directly with your own.

http://imgur.com/a/ZMVgq

Silverware Golem:

This is trumps bolster deck from back when the expansion was first available, it works consistently and i'll link Trumps video so you can see how it works :D

http://www.hearthpwn.com/decks/607396-heroic-silverware-golem-protect-the-king

http://imgur.com/a/YdJxU

Here's the best Magic Mirror deck

Link to original post with explanation but basically mill him Kappa:

http://www.hearthpwn.com/decks/606210-heroic-magic-mirror-easy-mill

http://imgur.com/a/Sz53g

Julianne:

A basic Zoo Warlock, flood the board and make trades. Has charges and Power Overwhelming for burst damage. Add soulfire and other cards if you'd rather removal.

http://imgur.com/a/vzxzQ

Big Bad Wolf:

Trade minions into his to get bigger deck rattle summoned minions and use n'zoth to resummon all your minions not as 1/1's. Explosive traps to deal with his opening wolves.

http://imgur.com/a/bhA4j

Crone:

Go here for explanation: http://www.hearthpwn.com/decks/612030-heroic-crone-1st-attempt

Free Medivh with Anyfin Paladin: http://imgur.com/a/Aotlu

The gameplan is to stall early on until you managed to stabilize the board, then kill Nazra when you have the Anyfin(s) in your hand to fill the board after Malchezaar used Twisting Nether. Mulligan for the early-game stall cards or oozes. No need to keep murlocs in your opening hand since you'll draw them eventually with the help of your card draws.

This seems to be pretty consistent overall, although I'm not sure if the deck is optimal yet. There's a bit of chance to lose in the Nazra fight if your early draw isn't good, maybe about 20% chance to lose, though the defeat is usually quick.

One thing that I'm still not sure is whether it's better to play your first Anyfin before or after killing Nazra. If you play it before killing Nazra, you can fill the board with more murlocs after Malchezaar pops up. But if you used your first Anyfin after killing Nazra, your board can last longer (since you can refill the board again with 2nd Anyfin) and you can get a random 10-drop for your first Anyfin.

Sometimes, I used the first Anyfin while Nazra is still alive to clear the board if Nazra have a bunch of minions. If this isn't necessary though, I usually keep my two Anyfins in hand for Malchezaar. It's a lot safer if you already have both Anyfins in hand when you're killing Nazra.

As for the card draw in this deck, seems I seldom have a lack of card draw and I tend to reach near fatigue pretty quickly. Divine Favor is really useful before turn 9 or 10 because at that point Nazra tends to hold a lot of cards in her hand. Previously, I was thinking of putting Coldlight Oracles but it seems I end up reaching fatigue too quickly with it.

The two 8-mana class legendaries in this deck (Tirion and Lightlord) isn't necessary though they've helped quite a lot. (Can be easily replaced with cheap cards such as Ancient of Blossoms, Sen'jin Shieldmasta or Antique Healbot)

I haven't tried the Ancestral Spirit + Kelthuzad that Zypher used in his run. There could be a bunch of things tried out on Shaman especially with the new elementals, though my gut feeling is that it can't be more reliable than the Anyfin Paladin deck (it'll be good if someone prove me wrong ;) ).

Magic Mirror with Unlicensed Apothecary: http://imgur.com/a/jx3To

Gameplan is to give the boss a copy of the Apothecary, which allows a lot of damage that can be easily dealt to the boss. Sense Demons make this deck consistent, I often draw an Apothecary or Sense Demons by turn 5. Most of my wins seems to be within 9 turns, with the fastest being a 5-turn win.

The deck is consistent overall, but it turns out to be hard to play optimally. There's a bit of chance to lose though most of my losses are because of my misplays.

Note that one of the three secrets used by Magic Mirror is a Mirror Entity. This allows you to give the boss an extra Apothecary and could make the fight a lot quicker.

I've put Sacrificial Pact in the deck which is meant to be used on my own Apothecary. I've also put Leeroy Jenkins since he will give three minions to the boss, although Jenkins isn't necessary at all for this deck.

Crone: http://imgur.com/a/BKhb9

The gameplan still depends on Inner Fire, but Shadow Visions it's much easier to draw an Inner Fire now and you still can't lose even if you don't draw your Inner Fire on the first several turns . This deck is a lot more minion-based than what's used in Zypher's run. Deathrattle minions are normally used for taunts while the low-cost high-attack minions could deal lots of damage since they have charge.

I'll still mulligan for any of the spells. Even without Inner Fire, having Divine Spirit in your opening hand is more than enough to ensure Dorothy's survival.

Silverware Golem with Paladin: http://imgur.com/a/MnRcK

This deck works similar to the deck I've used in heroic Giantfin for my heroic LoE run. Both Silverware and Giantfin have similar mechanics where they can keep filling their board with strong 1-hp minions every turn.

Gameplan is to stall until you can put out the Volcanic Drake/Grim Patron/Baron Geddon for the board presence. Once you control the board, the boss won't have a way to take back the board advantage.

I normally mulligan for an early board clear and a card draw (Divine Favor or Solemn Vigil). Having at least one of the card draw is really important, since the draws will make it easy to clear the board everytime and gives you the minions required for the board presence in late game.

This deck isn't that fast, it also have a bit of chance to lose although probably with less than 10% chance of losing. I've also tried Patron Warrior which is what commonly shown on the heroic guides. It can be fast when things gone right and you managed to put Frothing Berserker or Grim Patrons early on, but I don't think this deck can be consistent since you need good early draws.

Shade of Aran: http://imgur.com/a/Jleg1

Uses Shaman instead of Mage. Shaman is significantly faster and more consistent than Mage since they have more burst spells and the spells are cheaper too. Normally got lethal within the first 8 turns.

Note that this boss will always use his Flame Wreath secret on turn 3, so having one of the anti-secret cards by turn 4 helps a lot.

For these bosses, I'll use decks similar to what Zypher's uses but with some optimisations to make it more consistent (and hopefully faster).

Julianne: http://imgur.com/a/nlKtC Curator: http://imgur.com/a/TxdiK Illhoof: http://imgur.com/a/I4veA Netherspite: http://imgur.com/a/SFQDW

On Julianne and Curator, there are probably quite a lot of other good ways to tackle these bosses. The curator deck is the one that I feel isn't optimal at all since it still normally takes 11+ turns to win, but at least the mage cards is good in making the match consistent. Although for now I don't feel like experimenting a lot on Curator.

For Big Bad Wolf and Nightbane, I'll use different classes (Druid and Warrior), but the gameplan is still straightforward. (And I doubt both decks are optimal)

Big Bad Wolf: http://imgur.com/a/wPVOM Nightbane: http://imgur.com/a/m9U2C

Nightbane still have a very small chance to lose, maybe using priest will be more consistent (although I haven't tried it) but warrior's burst cards and weapons seem to make this boss goes significantly faster.

Here's the decklist used by Tsubaki during his run on 'RTA in Japan' marathon last December (here's the run VOD www.twitch.tv/videos/213219066 )

AAEBAZICBJ8Dgg6FF57BAg1AVtUB6QG4A/sG+Af7DJAO/A+xEYStAvfMAgA= Silverware AAEBAf0GAq8EkbwCDqMBiAXcBsQIkA78D/0RhK0Clr0Cj8cC58sCxcwCos0C+NACAA== Magic Mirror AAEBAaToAgL1BbnBAg7zBbEI2Q3qD+wP7Q+FENMTuMcC48sC+NIC+9MCteYCt+cCAA== Julianne AAEBAR8Kwgb4CIIOqKsC4KwC/70Cws4C/eECtuoC8eoCCtgTx64CxsICps4C5tMC5+EC0OcC7eoC1+sC3esCAA== Big Bad Wolf AAEBAa0GAu0Fjw4O+wH4ApME+AfRCvIM+g2prQKJtALwuwLRwQLYwQKrwgLFxwIA The Crone AAEBAf0GBLYHwg/o5wLb6QINowG7A+EHxAjMCP0R3bwC58sCos0C980Cps4C8tAC/dACAA== Curator AAEBAZICECTFBMIG+QyCDvoO7BWUF6irAp+wAuC7Aqe9AuLHAsLOAv3hAvHqAgfTAeEH3haHzgKmzgLn4QLd6wIA Nightbane AAEBAf0GBIgF7QWaB5G8Ag2jAYUD9QXlB/gHxAivrAK8tgLexALfxALnywLy0AKL5QIA Illhoof AAEBAYO6AgK0Ae0FDpwC7QK9BJsFxAXGBYgHhgn6D/W7Avq9AvfBAvjBAvzBAgA= Aran AAEBAY0WAq8E+g4OrAGfA5YF4ga8CP4NiA+QFMMUhLsCl8EC38QChM4C1M4CAA== Netherspite AAEBAf0GBsIP1hHpEcXMAqLNApfTAgyKAasGjg7wEf6sAurBAubCAsrDAtPFApHiAujnApboAgA= Free Medivh!

in image format: (might be slightly different than what the code shows, code is more updated): https://imgur.com/a/sOOr9pw

Mirin used a different deck for Silverware, using Warlock: AAEBAcn1AgKX0wLb6QIO0wG4A/cE+wa2B/gHjg6QDvwPhK0C980C+9MC/OUC6OcCAA== he also used Taunt warrior for Curator: AAEBAYwWBLmyAtPDAsnHApvLAg2KAbgD/g2QDoUQrRXOFtKuAtCvApvCAubCAsrDAt/EAgA=

Some notes:

• Tsubaki's Mill Druid are made for safety, so it's not that fast. Mirin happen to got a really good time in his JRTA (and PB) run
• They used Majordomo + Treachery for Free Medivh!. Note that Free Medivh is now bugged where you can use Sac Pact to instantly kill Malchezaar.

Forgot to post my newest Karazhan strats here. Links posted below are the ones used on my 48:06 run. Decklist: https://imgur.com/a/1R2RHEQ Deckcodes: https://pastebin.com/rFi6i7Xt

Curator: Shaman have lots of cheap control tools to deal with Curator's early game, removals if he got a huge minion from a random effect, and mid-cost huge minions to quickly finish off the boss once you gain board control.

Finishing time usually ranges between 2:50-3:30, which seems to be an overall improvement compared to any other strats previously used for a speedrun. There's still a small chance to lose because of the random nature of this boss, I doubt you could avoid this because of the random nature of this boss.

There are lots of ways to beat this boss, although most quick ways might not be that consistent. Haven't experimented a lot though.

Free Medivh: My 48:06 run uses the Sac Pact bug, which was patched several days after that run. So I probably gonna move my run to a different category until more improvements are available in the future.

I made a deck using the Majordomo+Treachery stuff here: https://imgur.com/a/CeG9pz7 AAEBAf0GCJAHwg/WEekRxcwCl9MClugCoIADC4oB+AeODvUP/qwC5sICysMC08UC/dACx9MC6OcCAA== Still not as fast as I hoped, but it's mostly consistent. Still a bit of chance to lose with a bad early game. Usually takes between 6-7 minutes, although could be as low as 5 minutes if I'm really lucky.

Silverware Golem: There are three classes that I think are decent for this boss: Warrior, Paladin and Warlock. If you want to make this boss really consistent, you can just fill your deck with all the board clears available. Although this playstyle won't be fast.

To make this deck faster, you've to put minions that could generate lots of value for cheap cost, such as Sea Giant, Volcanic Drake or Grim Patron. The more of these minions you put though, the deck might be less consistent because there'll be less defensive tools.

The deck that I use seems to have around ~70% winrate in practice (although worse for my actual run attempts). I choose warrior because it's easier to summon multiple Grim Patrons compared to Paladin/Warlock, and Frothing Berserker can cause quick kills too. Tar Lord also turns out to be pretty good since it can easily kill lots of mid-size minions.

There are lots of ways you can optimize this deck. I doubt my version is optimal, but I'm not sure if there's any optimal way since it's usually a matter of trade-off between speed and consistency.

Julianne: I tried to optimize Odd Paladin which was used by One1_won, I got turn 7-8 kills about 75% of the time.

Put in Dancing Swords and Stoneskin Basilisk because I think they're good in dealing with an early Fierce Monkey. Some of the 1-drops are put here just so I can get a 1-drop on first turn more often.

Haven't tried lots of other decks though, and there could be bunch of other decks that might be as fast since this boss is easy and can be beat with lots of decks.

Minor improvements in other decks:

• Illhoof: I'm still using Priest instead of Defile Warlock, since Warlock could be much slower if I don't get my Defile early.
• Crone: Put some 1-drops because I often have spare 1-mana that I can use at most turns. Also put in C'thun Disciple/Spring Rockets because they're really flexible.
• Shade of Aran: Added more card draws, not sure why the older version uses Shadowstep. Rogue is faster than Shaman on average.
• Netherspite: Putting in more charge minions like Wolfrider and Bluegill Warrior seems to help quite a lot with making the decks more often to finish below turn 9.

Chess: Got about 2/3 wins in Chess usually, here's what I usually do in the first three turns:

• turn 1 do nothing, opponent will play double Pawns with coins
• turn 2 play 1 Pawn, opponent will usually play only 1 pawn next turn
• turn 3 play 3x Pawns or a Rook, this will give the most double-attacks if the opponent only have 3 Pawns by turn 2 As for the AI manipulation, AI won't use hero power on a 1-health Pawn or Bishop. Opponent will still use it on a 2-health Pawn though, and still use it for a 1-health Knight or Rook.

Prologue: This is the single thing that make me dislike running heroic Karazhan. (╯°□°）╯︵ ┻━┻ Crappier new secrets and average legendary minion's stats seems to reduce the consistency and speed a lot. Currently, I probably have around 20-30% winrate with an average time of above 7:30. While last year, I usually got around 70% winrate and average finish time of around 6:30.

Magic Mirror with Mo'arg Artificier + Soulbound Ashtongue: cdn.discordapp.com/attachments/283236838347505666/909414845022081044/unknown.png AAEBAcn1AgAP3AbOB/0Rj8cC58sCw/MC7awDv7kD474D6b4Dld4Dk+QDg/sDsZ8E56AEAA==

Summon Moarg Artificier and Soulbound Ashtongue on his side so we could deal super-high damage spell to him on one hit.

I'm using Warlock since it has minion tutor draws (Sense Demons / Free Admission / Dark Portal), lots of cheap damage spells for the final kill, and lots of cheap board clears for his minions.

Haven't tested a lot of this, usually takes turn 6-9. Probably faster than old Apothecary strats since the Apothecary triggers a lot of animation, but I haven't done any proper comparison tests.

Free Medivh with Grand Finale Mage (and Renathal): https://imgur.com/a/cfZzggL AAEBAf0EBKCAA/bWA+efBJfvBBKKAfgHysMC08UCx9MClugCtPwCv6QD9KsD+7AD+N0D/N0D7ukDwPkDk4EE/J4ErJ8ExqAEAA==

Set up 8/8 elementals, cast Counterspell before killing Nazra, then kill Malchezaar immediately afterwards.

Still a bit of chance to lose with a bad early game. Renathal helps this deck a lot, I've tried making this deck before Renathal and only have about 50% winrate previously.

Getting Flame Ward early is usually important, so I've put a lot of secret tutors, and the tutors are also helpful to get Counterspell later on.

Not fully sure on which tech cards I need to put in the deck. Can't put too much healing as I need enough card draws on the deck, and don't need lots of healing if we have a good early game.

Edit - Renathal nerf update: The 5-HP decrease doesn't seem to really matter. I still find it more consistent to use Renathal instead of using a 30-card deck, as the 40-card deck allows me to put more mid-game defensive minions without removing the combo pieces or card draws.

Silverware Golem with Marrowgar (Triple Unholy) Death Knight: cdn.discordapp.com/attachments/283236838347505666/1056914510348288020/image.png

Marrowgar can build a huge board without any setups. So all we need to do is to just keep defending until we got Marrowgar and probably at least 12 corpses. Usually win on 1-3 turns after playing Marrowgar, depending on how many corpses you use and if you have Platebreaker or not.

One reason why DK works well is the Unholy 4 & 5 mana cards on my deck. They're very useful for defending/clearing small tokens, and to generate corpses for Marrowgar.

Don't need card draws in this deck as the Marrowgar tutors (Polkelt & Taelan) are usually enough to set up the combo on time. (Edit: I've added a bit more card draws as there's still chances of losing due to not drawing Marrowgar on time. I've replaced Icy Touch with Chillfallen Baron on my final decklist.)

I've tried to use The Scourge for my DK deck, but The Scourge usually creates a mediocre board, with lots of minions having 3 or less attack.

I've also tried few other decks (Mechathunlock, Venomizer + Missile Launcher, old warrior strats) and none of them works well for this boss. For combo decks, even just spending one turn to setup the combo (such as playing Hemet) could potentially kill me with how quickly the enemy's board can grow.