I have been enjoying Turn-90 Fatigue Death Knight (feat Adaptive Amalgam). The deck tutors Amalgams with Troubled Mechanic and The Curator. The Headless Horseman 3-damage hero power is most consistently the win condition. Patiently after 50 turns pumpkin power does 150 damage. Use Bloated Leeches and Airlock to reach 60-90 hero health and average 70.
…you shall know my cruelty firsthand
Nightmare Lord, Xavius can bestow Amalgam with a Dark Gift. Strong or situational options “Reborn” and “Summon 2/2 Copy.”
Pair “Bundled Up” (+4 Health & Taunt) with Poison Breath. The caustic hippo “mini” Tortolla clears big bad creatures and is durable early. Bundled Up being one Amalgam’s possible intermediate phase before full potential. No two exact games… unless you want them to be 
Previous posts have shared experiences with Adaptive Amalgam.
Key Interactions
If active upon death, Divine Shield will persist after death when shuffled (e.g. Assassinate: destroy an enemy minion). If Divine Shield is consumed the enchant condition flips: True/False. Amalgam has Divine Shield “keyword” but specific keyword “deactivation” and trigger sequences may keep or remove enchants. When drawn and played Amalgam would no longer have Divine Shield.
THIS creature keeps ALL positive and negative conditions “instantly” but concordantly with trigger sequencing rules.
Poison and Lifesteal are kept after contact and death. These enchants stay unlike Battleground’s single hit Poison (i.e., damage). BG Poison and Standard Poison may be completely different enchants regardless of shared name and effect.
Direct attack and health increases and decreases (e.g., 0/0) are persisting enchants. General Aura effects do not persist to my knowledge. Auras and other ability/stat bestowing mechanics could exist.
I don’t know
Persisting Enchantments
[1] Orbital Moon (Lifesteal, Taunt, !Reborn)
\ Situation !Reborn: recover Amalgam
\ “1” non-draw Amalgam blocks fatigue
\ Loss Conditions: burn, silence, stolen, no Fatigue Blocker, Final Boss Turn-75 Kil’Jaedan
\ Stolen Amalgam enchants persist
\ Stolen Fatigue Blockers: best insta-loss prevention “1/2 basic” non-draw Amalgam
\ Non-Draw Fatigue Blocker: play, clear and shuffle into deck
\ Spicy: Floppy Hydra blocker reaches 512 attack—eventually
[1] Lesser Spinel Spellstone (+3/3 Undead)
[2] Braingill (Murloc’s gain “Draw a card”)
[3] Threads of Despair (Deal 1 to ALL minions)
[3] Escape Pod (+1/1 and Rush)
[4] Helm of Humiliation (+/- 5/5)
[5] Amateur Puppeteer (+3/3 Undead)
Semi-Persisting Enchants
[4] Nightmare Lord, Xavius {
\ Situation !Reborn: fatigue or recovery
\ Dark Gift — Living Nightmare
\\ Summon a 2/2 Copy
\\ New Copy no Dark Gift
\\ New Copy == Secret: Redemption
\\ However “copies” pre-Dark Gift enchants
\ Dark Gift — Persisting Horror
\\ Reborn full health and enchants
\\ !Reborn == New Copy
Game Loss: Nightmare Lord, Xavius
\ Dark Gift — Sweet Dreams
\\ +4/+5 Place on top of deck!
\\ Destroys ALL enchants previously bestowed
\\ Place action removes enchants, not Dark Gift
My motivation came from confusion about Reborn and Dark Gifts. I had been surprised when an Amalgam (Poison Breathe & Threads of Despair) was subsequently Dark Gifted Living Nightmare. The summoned “New Copy” had pre-Dark Gift enchants (Poison & 1 Damage AoE). Future enchants given after the Dark Gift are not bestowed. Nightmare Lord, Xavius battlecries can chain on same Amalgam, but I’m unsure of trigger sequences and enchant persistence.
Things and thoughts since playing the deck and snowballing doom hippos. If you have experience playing with or against hippo or this deck archetype, let’s update the history!
Below are two of the four variants I play. The other relies on Helm of Humiliation for stronger late game board clears. The last two of the four decks are designed for my EU f2p account.
Troubled Mechanic DK
I frequently test new cards and strategy. Currently I dropped both Corpse Explosion for Dreamplanner Zephrys and Lesser Spinel Spellstone.
2x (1) Adaptive Amalgam
1x (1) Lesser Spinel Spellstone
2x (1) Morbid Swarm
2x (1) Orbital Moon
2x (2) Braingill
2x (2) Infested Breath
2x (2) Poison Breath
2x (2) Troubled Mechanic
1x (3) Dreamplanner Zephrys
2x (3) Escape Pod
2x (3) Threads of Despair
1x (4) Nightmare Lord Xavius
2x (4) Sanguine Infestation
1x (5) The Curator
2x (6) Airlock Breach
2x (6) Hideous Husk
1x (6) The Headless Horseman
1x (0) Zilliax Deluxe 3000
1x (4) Twin Module
1x (5) Perfect Module
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The Helm DK
2x (1) Adaptive Amalgam
2x (1) Morbid Swarm
2x (1) Orbital Moon
2x (2) Braingill
2x (2) Infested Breath
2x (2) Poison Breath
2x (3) Chillfallen Baron
2x (3) Threads of Despair
2x (4) Ghouls’ Night
1x (4) Helm of Humiliation
1x (4) Nightmare Lord Xavius
2x (4) Sanguine Infestation
1x (5) Corpse Explosion
1x (5) The Curator
2x (6) Airlock Breach
2x (6) Hideous Husk
1x (6) The Headless Horseman
1x (0) Zilliax Deluxe 3000
1x (4) Twin Module
1x (5) Perfect Module
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