Slay the Spire 2 Wiki

Card

Necro Mastery

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

Necro Mastery is a rare Necrobinder Power that enhances the Necrobinder's core mechanics, amplifying the effectiveness of Summon, Doom, and Soul interactions. This versatile Power supports all three of the Necrobinder's archetypes simultaneously.

Necro Mastery benefits Osty/Summon builds through enhanced Summon effects from Invoke and Grave Warden. It strengthens Doom builds by amplifying Blight Strike and End of Days. And it powers up Souls/Blood Magic through better Graveyard retrieval from Dredge and Seance. This cross-archetype support makes Necro Mastery one of the Necrobinder's most flexible rares.

Necro Mastery is valuable in any Necrobinder build because it enhances whichever archetype you have committed to. Against bosses where you need maximum output from your chosen strategy, Necro Mastery provides the amplification needed. The Necrobinder rewards players who master all three of her interlocking systems, and Necro Mastery is the card that ties them together.

Details

Card TypePower
Cost2
RarityRare
TargetSelf
Effect TextSummon 5. Whenever Osty Loses HP, ALL Enemies Lose That Much HP As Well.

Character

NoindexNo
In GameConfirmed

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Quick Facts

Type
Card
Confidence
Medium
Verified
Mar 12, 2026