Bone Shards•Attack

Is Bone Shards good in Slay the Spire 2?

Bone Shards is an uncommon Necrobinder attack in Slay the Spire 2. In combat it resolves as: If Osty is alive, he deals 9 damage to ALL enemies and you gain 9 Block. Osty dies. It currently underperforms most alternatives, sitting at D tier in our Slay the Spire 2 card rankings.

Across 15 recorded runs, decks running it win 7.7% of the time, trailing the 12.6% average by 4.9%. It’s a more selective pick, turning up in just 2.9% of decks that could run it. Necrobinder players keep it in 8.7% of their runs, so it’s a familiar sight in those decks. On average it shows up 1.1 times in the decks that take it.

It performs best next to Greed — together they post a +42.3% swing in win rate. It also has strong chemistry with the relic Bone Flute, which moves its win rate by +25.6%. At 1 energy, it’s upgraded in 17.6% of runs and usually joins the deck around floor 9.

Upgraded, it gains +3 OstyDamage, +3 Block, which is why so many decks invest a rest-site upgrade in it. That’s 1 wins, 12 deaths, and 2 abandoned runs with it in the deck. The encounter that most often ends a run carrying it is Infested Prisms Elite, which closes out 13.3% of its appearances. Read on for Bone Shards’s complete synergy, class, and threat breakdown to decide whether it earns a slot in your Necrobinder run.

Best Cards to Pair with Bone Shards

Ranked by win-rate lift, Bone Shards performs best alongside Greed (+42.3%), Death's Door (+25.6%), and Bury (+25.6%).

Greed+42.3%3 runsDeath's Door+25.6%3 runsBury+25.6%3 runsCalcify+25.6%3 runsCapture Spirit+25.6%3 runsBlight Strike+25.6%3 runs

Based on small co-occurring samples — treat these as early signals, not final verdicts.

Bone Shards Win Rate by Class

Bone Shards is drafted only by the Necrobinder, where it holds a 7.7% win rate across 15 runs.

The Necrobinderappears in 8.7% of its runs (15 tracked)

Best Relics for Bone Shards

Bone Shards pairs best with the relics Bone Flute (+25.6%), Bound Phylactery (+0.6%), and Venerable Tea Set (-7.7%), ranked by win-rate lift.

Bone Flute+25.6%3 runsBound Phylactery+0.6%14 runsVenerable Tea Set-7.7%3 runsPotion Belt-7.7%3 runsPrecarious Shears-7.7%3 runsBronze Scales-7.7%4 runs

Based on small co-occurring samples — treat these as early signals, not final verdicts.

Bone Shards Card Details

Bone Shards is an uncommon attack costing 1 energy; it’s upgraded in 17.6% of runs and usually picked up by floor 9.

If Osty is alive, he deals 9 damage to ALL enemies and you gain 9 Block. Osty dies.

Upgrade: +3 OstyDamage, +3 Block

What Ends Runs with Bone Shards

Bone Shards’s most common run-enders are Infested Prisms Elite (13.3%).

• Infested Prisms Elite13.3% of runs

See Also

Compare Bone Shards with the rest of the best Slay the Spire 2 cards, relics, and classes below.