Necro Mastery

NecrobinderPowerRare
Summon 5.
Whenever Osty loses HP,
ALL enemies lose that much HP as well.

Summon 5, 8 upgraded: Osty appears with that much HP, or gains that much Max HP if already out.

  • Power: whenever Osty loses HP, every enemy loses that much HP too, as unblockable, unpowered loss that ignores Block, Strength and Vulnerable.
  • Two copies: double it.
  • Buffer: Osty absorbs unblocked Attack damage aimed at you, so every hit that gets through your Block is mirrored onto the whole enemy side.
Character
Necrobinder
Type
Power
Rarity
Rare
Cost
2 Energy
Target
Yourself

When to take Necro Mastery

Take it for a big-Osty Necrobinder, since with Reanimate or Pull Aggro he can eat heavy damage and deal it back to every enemy. Best against multi-hit and multi-enemy fights.

Cards that synergize with Necro Mastery

Reanimate
Skill
3
Summon 20.
Exhaust.
Reanimate and Bodyguard keep Osty large.Summon 20.
Exhaust.
Bodyguard
Skill
1
Summon 5.
Reanimate and Bodyguard keep Osty large.Summon 5.
Spur
Skill
1
Retain.
Summon 3.
Osty heals 5 HP.
Spur heals him 5 so he can take more.Retain.
Summon 3.
Osty heals 5 HP.
Bone Shards
Attack
1
If Osty is alive, he deals 9 damage to ALL enemies and you gain 9 Block.
Osty dies.
Bone Shards spends him for damage and Block once he has done his work.If Osty is alive, he deals 9 damage to ALL enemies and you gain 9 Block.
Osty dies.
Unleash
Attack
1
Osty deals 6 damage.
Deals additional damage equal to Osty's current HP.
Unleash scales with the HP you are protecting.Osty deals 6 damage.
Deals additional damage equal to Osty's current HP.
Squeeze
Attack
3
Osty deals 25 damage.
Deals 5 additional damage for ALL your other Osty Attacks.
Squeeze counts on Osty, whom Necro Mastery SummonsOsty deals 25 damage.
Deals 5 additional damage for ALL your other Osty Attacks.
Flatten
Attack
2
Osty deals 12 damage.
This card costs 0 if Osty has attacked this turn.
Flatten counts on Osty, whom Necro Mastery SummonsOsty deals 12 damage.
This card costs 0 if Osty has attacked this turn.
Protector
Attack
1
Osty deals 10 damage.
Deals additional damage equal to Osty's Max HP.
Protector counts on Osty, whom Necro Mastery SummonsOsty deals 10 damage.
Deals additional damage equal to Osty's Max HP.
Rattle
Attack
1
Osty deals 7 damage.
Hits an additional time for each other time he has attacked this turn.
Rattle counts on Osty, whom Necro Mastery SummonsOsty deals 7 damage.
Hits an additional time for each other time he has attacked this turn.
Snap
Attack
1
Osty deals 7 damage.
Add Retain to a card in your Hand.
Snap counts on Osty, whom Necro Mastery SummonsOsty deals 7 damage.
Add Retain to a card in your Hand.
Afterlife
Skill
1
Summon 6.
Exhaust.
Afterlife Summons Osty, whom Necro Mastery counts onSummon 6.
Exhaust.
Poke
Attack
0
Osty deals 6 damage.
Poke counts on Osty, whom Necro Mastery SummonsOsty deals 6 damage.
High Five
Attack
2
Osty deals 11 damage
and applies 2 Vulnerable
to ALL enemies.
High Five counts on Osty, whom Necro Mastery SummonsOsty deals 11 damage
and applies 2 Vulnerable
to ALL enemies.
Legion of Bone
Skill
2
ALL players Summon 6.
Exhaust.
Legion of Bone Summons Osty, whom Necro Mastery counts onALL players Summon 6.
Exhaust.
Sic 'Em
Attack
1
Osty deals 5 damage.
Whenever Osty hits this enemy this turn, Summon 3.
Sic 'Em counts on Osty, whom Necro Mastery SummonsOsty deals 5 damage.
Whenever Osty hits this enemy this turn, Summon 3.
Calcify
Power
1
Osty's attacks deal 4 additional damage.
Calcify counts on Osty, whom Necro Mastery SummonsOsty's attacks deal 4 additional damage.
Pull Aggro
Skill
2
Summon 4.
Gain 7 Block.
Pull Aggro Summons Osty, whom Necro Mastery counts onSummon 4.
Gain 7 Block.
Right Hand Hand
Attack
0
Osty deals 4 damage.
Whenever you play a card that costs or more, return this to your Hand from the Discard Pile.
Right Hand Hand counts on Osty, whom Necro Mastery SummonsOsty deals 4 damage.
Whenever you play a card that costs or more, return this to your Hand from the Discard Pile.
Cleanse
Skill
1
Summon 3.
Exhaust 1 card from your Draw Pile.
Cleanse Summons Osty, whom Necro Mastery counts onSummon 3.
Exhaust 1 card from your Draw Pile.
Dirge
Skill
X
Summon 3 X times.
Add X Souls into your Draw Pile.
Exhaust.
Dirge Summons Osty, whom Necro Mastery counts onSummon 3 X times.
Add X Souls into your Draw Pile.
Exhaust.
Fetch
Attack
0
Osty deals 3 damage.
If this is the first time this card has been played this turn, draw 1 card.
Fetch counts on Osty, whom Necro Mastery SummonsOsty deals 3 damage.
If this is the first time this card has been played this turn, draw 1 card.
Invoke
Skill
1
Next turn, Summon 2 and gain .
Invoke Summons Osty, whom Necro Mastery counts onNext turn, Summon 2 and gain .
Devour Life
Power
1
Whenever you play a Soul, Summon 1.
Devour Life Summons Osty, whom Necro Mastery counts onWhenever you play a Soul, Summon 1.
Sacrifice
Skill
1
Retain.
If Osty is alive, he dies and you gain Block equal to double his Max HP.
Sacrifice counts on Osty, whom Necro Mastery SummonsRetain.
If Osty is alive, he dies and you gain Block equal to double his Max HP.

Relics that synergize with Necro Mastery

Phylactery Unbound
Phylactery Unbound adds HP every turn.At the start of each combat, Summon 5. At the start of your turn, Summon 2.
Bone Flute
Bone Flute counts on Osty, whom Necro Mastery SummonsWhenever Osty attacks, gain 2 Block.
Bound Phylactery
Bound Phylactery Summons Osty, whom Necro Mastery counts onAt the start of your turn, Summon 1.
Permafrost
Permafrost triggers on Powers played, and Necro Mastery is oneThe first time you play a Power each combat, gain 7 Block.
Lost Wisp
Lost Wisp triggers on Powers played, and Necro Mastery is oneWhenever you play a Power, deal 8 damage to ALL enemies.
Mummified Hand
Mummified Hand triggers on Powers played, and Necro Mastery is oneWhenever you play a Power, a random card in your Hand is free to play that turn.
Game Piece
Game Piece triggers on Powers played, and Necro Mastery is oneWhenever you play a Power, draw 1 card.
Intimidating Helmet
Intimidating Helmet triggers on cards that cost 2 or more, and Necro Mastery is oneWhenever you play a card that costs or more, gain 4 Block.
✦
Sic 'Em
Attack
1
Osty deals 5 damage.
Whenever Osty hits this enemy this turn, Summon 3.
Spur
Skill
1
Retain.
Summon 3.
Osty heals 5 HP.
Devour Life
Power
1
Whenever you play a Soul, Summon 1.
Calcify
Power
1
Osty's attacks deal 4 additional damage.
Flatten
Attack
2
Osty deals 12 damage.
This card costs 0 if Osty has attacked this turn.
High Five
Attack
2
Osty deals 11 damage
and applies 2 Vulnerable
to ALL enemies.
Legion of Bone
Skill
2
ALL players Summon 6.
Exhaust.
Pull Aggro
Skill
2
Summon 4.
Gain 7 Block.

Changes by version

  1. 20 Nov 2025Bug fixInternal playtest
    Necro Mastery card's Summon hovertip now properly shows its Summon amount, and the word Summon is now properly keyworded in its description
  2. 13 Nov 2025ReworkInternal playtest
    Reworked cards
  3. 8 May 2025ArtInternal playtest
    Added portrait art
All 8 patch notes5 older
  1. 20 Feb 2025Bug fixAfterlifeInternal playtest
    Necro Mastery card now properly buffs Afterlife card's next turn Summon amount
  2. 30 Jan 2025Necromancy3(4)2(3)Internal playtest
    Necromancy decreased from 3 to 2 (upgraded 4 to 3)
  3. 16 Jan 2025RarityUncommonRareSummon2(3)3(4)Internal playtest
    Rarity changed from Uncommon to Rare and Summon increased from 2 to 3 (upgraded 3 to 4)
  4. 9 Jan 2025Bug fixInternal playtest
    Necro Mastery card now affects the summon value for Nine Lives card if played beforehand
  5. 1 Nov 2024AddedInternal playtest
    Added to the game

Internal playtest notes are from before the Early Access release. Names and numbers in them can differ from the game today.

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