Version

Flatten

NecrobinderAttackCommon
Osty deals 12 damage.
This card costs 0 if Osty has attacked this turn.

Osty hits the target for 12. The cost drops to 0 for the turn whenever Osty has already attacked this turn; the check runs after every Osty attack on every copy wherever it sits, draw pile included, so a Flatten drawn later in the same turn is already free. If Osty is missing the card does nothing. Upgraded, 16 damage.

Character
Necrobinder
Type
Attack
Rarity
Common
Cost
2 Energy
Target
One enemy

When to take Flatten

Grab a copy in Act 1 for any Osty deck; open each turn with a cheap Osty attack first and this becomes a free 12 most turns. Upgrade it, since 16 for free is a rare level rate.

Cards that synergize with Flatten

Poke
Attack
0
Osty deals 6 damage.
Poke and Fetch are the free Osty attacks that unlock it.Osty deals 6 damage.
Fetch
Attack
0
Osty deals 3 damage.
If this is the first time this card has been played this turn, draw 1 card.
Poke and Fetch are the free Osty attacks that unlock it.Osty deals 3 damage.
If this is the first time this card has been played this turn, draw 1 card.
Unleash
Attack
1
Osty deals 6 damage.
Deals additional damage equal to Osty's current HP.
Unleash does the same from the starter deck.Osty deals 6 damage.
Deals additional damage equal to Osty's current HP.
Calcify
Power
1
Osty's attacks deal 4 additional damage.
Calcify adds damage to every Osty hit.Osty's attacks deal 4 additional damage.
Rattle
Attack
1
Osty deals 7 damage.
Hits an additional time for each other time he has attacked this turn.
Rattle gets an extra hit for each earlier Osty attack, so play it after.Osty deals 7 damage.
Hits an additional time for each other time he has attacked this turn.
Reanimate
Skill
3
Summon 20.
Exhaust.
Reanimate Summons Osty, whom Flatten counts onSummon 20.
Exhaust.
Afterlife
Skill
1
Summon 6.
Exhaust.
Afterlife Summons Osty, whom Flatten counts onSummon 6.
Exhaust.
Bodyguard
Skill
1
Summon 5.
Bodyguard Summons Osty, whom Flatten counts onSummon 5.
Legion of Bone
Skill
2
ALL players Summon 6.
Exhaust.
Legion of Bone Summons Osty, whom Flatten counts onALL players Summon 6.
Exhaust.
Necro Mastery
Power
2
Summon 5.
Whenever Osty loses HP,
ALL enemies lose that much HP as well.
Necro Mastery Summons Osty, whom Flatten counts onSummon 5.
Whenever Osty loses HP,
ALL enemies lose that much HP as well.
Pull Aggro
Skill
2
Summon 4.
Gain 7 Block.
Pull Aggro Summons Osty, whom Flatten counts onSummon 4.
Gain 7 Block.
Cleanse
Skill
1
Summon 3.
Exhaust 1 card from your Draw Pile.
Cleanse Summons Osty, whom Flatten 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 Flatten counts onSummon 3 X times.
Add X Souls into your Draw Pile.
Exhaust.
Sic 'Em
Attack
1
Osty deals 5 damage.
Whenever Osty hits this enemy this turn, Summon 3.
Sic 'Em Summons Osty, whom Flatten counts onOsty deals 5 damage.
Whenever Osty hits this enemy this turn, Summon 3.
Spur
Skill
1
Retain.
Summon 3.
Osty heals 5 HP.
Spur Summons Osty, whom Flatten counts onRetain.
Summon 3.
Osty heals 5 HP.
Invoke
Skill
1
Next turn, Summon 2 and gain .
Invoke Summons Osty, whom Flatten counts onNext turn, Summon 2 and gain .
Devour Life
Power
1
Whenever you play a Soul, Summon 1.
Devour Life Summons Osty, whom Flatten counts onWhenever you play a Soul, Summon 1.
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 triggers on cards that cost 2 or more, and Flatten is oneOsty deals 4 damage.
Whenever you play a card that costs or more, return this to your Hand from the Discard Pile.
Danse Macabre
Power
1
Whenever you play a card that costs or more, gain 4 Block.
Danse Macabre triggers on cards that cost 2 or more, and Flatten is oneWhenever you play a card that costs or more, gain 4 Block.

Relics that synergize with Flatten

Bone Flute
Bone Flute gives 2 Block per Osty attack.Whenever Osty attacks, gain 2 Block.
Phylactery Unbound
Phylactery Unbound Summons Osty, whom Flatten counts onAt the start of each combat, Summon 5. At the start of your turn, Summon 2.
Bound Phylactery
Bound Phylactery Summons Osty, whom Flatten counts onAt the start of your turn, Summon 1.
Intimidating Helmet
Intimidating Helmet triggers on cards that cost 2 or more, and Flatten is oneWhenever you play a card that costs or more, gain 4 Block.
✦
High Five
Attack
2
Osty deals 11 damage
and applies 2 Vulnerable
to ALL enemies.
Poke
Attack
0
Osty deals 6 damage.
Snap
Attack
1
Osty deals 7 damage.
Add Retain to a card in your Hand.
Bone Shards
Attack
1
If Osty is alive, he deals 9 damage to ALL enemies and you gain 9 Block.
Osty dies.
Fetch
Attack
0
Osty deals 3 damage.
If this is the first time this card has been played this turn, draw 1 card.
Protector
Attack
1
Osty 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.
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.

Changes by version

  1. 26 Feb 2026Damage14(18)12(16)Internal playtest
    Damage decreased from 14 to 12 (upgraded 18 to 16)
  2. 4 Dec 2025InterfaceRattleThe NecrobinderPokeNeowInternal playtest
    Rattle card now appears in the front of Necrobinder's Rattle/Flatten/Poke Neow card bundle
  3. 13 Nov 2025ReworkInternal playtest
    Reworked cards
All 19 patch notes16 older
  1. 6 Nov 2025Cost21Damage15(25)10(10)RarityUncommonCommonInternal playtest
    Cost changed from 2 to 1, Damage decreased from 15 to 10 (upgraded 25 to 10) and rarity changed from Uncommon to Common
    ChangeThe NecrobinderNeowAfterlifeRattleInternal playtest
    Changed Necrobinder's Flatten Neow Bundle: Afterlife card replaced with to Rattle
  2. 23 Oct 2025Bug fixOstyStrengthInternal playtest
    Flatten card now properly displays the extra damage that will be dealt by Osty's Strength
  3. 16 Oct 2025ReworkInternal playtest
    Reworked the card
  4. 18 Sep 2025Damage scaling3(4)2(3)Internal playtest
    Damage scaling decreased from 3 to 2 (upgraded 4 to 3)
  5. 4 Sep 2025Damage scaling5(8)3(4)Internal playtest
    Damage scaling decreased from 5 to 3 (upgraded 8 to 4)
  6. 21 Aug 2025ChangeThe NecrobinderNeowFetchInternal playtest
    Changed Necrobinder's Neow Bundle blessing: bundle with Fetch now instead includes Flatten
  7. 14 Aug 2025Base damage155Internal playtest
    Base damage decreased from 15 to 5
  8. 7 Aug 2025BuffInternal playtest
    Now checks each time you have Summoned this combat instead of this turn
  9. 31 Jul 2025TextInternal playtest
    Updated wording for Flatten card
  10. 24 Jul 2025ReworkInternal playtest
    Reworked the card
  11. 26 Jun 2025ReworkInternal playtest
    Reworked cards
  12. 12 Dec 2024RarityRareUncommonInternal playtest
    Rarity changed from Rare to Uncommon
  13. 1 Nov 2024DamageInternal playtest
    Now deals 5 damage to a single enemy 5(6) times
  14. 24 May 2024ReworkInternal playtest
    Reworked Flatten card
  15. 4 May 2024Upgraded cost32Internal playtest
    Damage decreased from 6 to 5 and cost changed from 3 to 2
  16. 8 Sep 2023DamageOstyInternal playtest
    Flatten card has been reworked; "Osty attacks 5 times." to "Osty deals 5(6) damage 5 times."

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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