Latest Heroic Naxx decks for now: Decklists: https://postimg.cc/gLqns33C Deckcodes: https://pastebin.com/SatfnRqU

Faerlina:

• Can't find a better way than to use Mech Paladin again. This deck still often get a turn 6-7 kill.
• Recent AI likes to use their face to hit your taunts, no matter how big your taunt is. This helps the fight even more.

Maexxna:

• Mechathunlock. Needs those self-kill cards to kill your own Bonelord.
• Obviously you'll want to have the board clears on your opening hand.
• I tried Quest Rogue a bit (like what Tsubaki done back in 2017) but can't make it consistent or quick enough.

Noth:

• Rivendare Hunter. Weak tempo from the boss so Hunter can easily survive.
• Note that he have 2x Counterspell in his deck.

Heigan:

• It's just a slightly modified deck from my old Warlock deck.
• Can't find a better consistent deck for now. I tried Mechathunlock or Marrowgar DK and both of them aren't more consistent or faster.

Loatheb:

• I used Mechathunlock for the consistency.
• Aim to kill Fen Creeper ASAP from opening hand (Corruption, Final Gasp, Doomsayer, Unstable Shadow Blast)
• I've put some self-kill cards as well because sometimes it's hard to kill your own Bonelord without it. Dark Pact also provides good healing.
• The old regular token decks could be faster with lucky highrolls, but could easily be slower as well if he didn't play his Spore cards. And it's also not as safe.

Razuvious:

• Stickyfinger Mage similar to my old deck.
• But I've added Depth Charge / Doomsayer because recent AI tend to have better board control somehow compared to 3 years ago.
• Using Priest (like Mipha's PB) could be faster if you highrolled, but I can't make it consistent enough.

Gothik:

• Using Marrowgar DK. Not the fastest deck, but it's the safest one I could find that doesn't go that slow.
• I can't make Quest Rogue consistent enough, and it's not always faster either if you don't get to finish the quest quickly.
• Tried Mechathunlock as well, but his Spectral minions could disrupt your Mechathun combo.

Four Horsemen:

• Use Sigil of Silence or Showstopper at the start. This DH deck isn't 100% safe because we need one of those within the first two turns.

• After silencing the horsemen, just keep playing taunts and attacking enemy's face. Usually will kill in turn 4 or 5.

• This deck is helped by how AI tend to use his weapon to attack any taunts on our board, no matter how low his health is.

• A safer alternative is to use the old 14-damage Priest combo AAEBAa0GAtYKw50DDpwC+AfRCrW7Are7AtHBAtLBAtD+AtGsA5nrA+jvA4f3A62KBIqjBAAA

Patchwerk:

• Stickyfinger Druid where the aim is to use Stickyfinger on turn 3.
• If can't play Stickyfinger on turn 3, can stall one more turn by using your armor cards (Claw, Gnash, Feral Rage) to get above 32 total health.
• Consistent deck, and is faster than the old mage deck.

Grobbulus:

• Mechathunlock works well. Normally you want to prioritise in clearing any minions to prevent him buffing it on the next turn.

• Suffocating Shadows is effective in clearing his Spectral Knights (he have 4 copies of it)

• Note that Arson Accusation will instakill any enemy because of Grobbulus' hero power.

• An alternative list is the BEES+Linecracker Druid combo (based on Hess's idea). Current AI tend to ignore your Linecracker, so it's easy to setup the combo. From my timing tests, this deck is faster if we got the combo done before turn-8 by using Biology Project. But a turn-8 win is slower than a turn-8/9 Mechathun combo. AAEBAZICAq+ABMmeBg7pAb/yAo/2AvCJA7mUA6+iA9WgBLClBK7ABJ3UBITvBI3vBOScBaueBgAA

Gluth:

• Two possible decks: Mechathunlock or the old Stickyfinger Mage
• A turn-7 Mage kill is about 20s faster than a turn-8 Mechathunlock kill. But Mechathun is usually safer as Gluth isn't guaranteed to draw his Jaws weapon.
• I'll use Stickyfinger Mage on the list above. Look at my 42:20 run for a Mechathunlock list.

Thaddius:

• Using the recent Warlock resurrect cards, the win condition is by summoning multiple Thaddiuses on turn 6+.
• Usually get a turn-9 kill, can get turn 8 with some luck.
• The deck contains mostly spells, so that Free Admission will guarantee a Feugen/Stalagg draw.
• I tried Mechathunlock and it's not so effective. Can't play the 4-mana board clear spells on Mechathun deck, and sometimes I can't kill my own Bonelord quickly.

Sapphiron:

• Rivendare Hunter. Weak tempo from the boss so Hunter can easily survive.

Kel'thuzad:

• Mechathunlock deck, with plenty of heals (such as Dark Pact) to counter his hero power.
• Hunter isn't consistent enough because there's no healing against Kelthuzad's hero power, even though this boss have a weak tempo.