Thunder•Power

Is Thunder good in Slay the Spire 2?

Thunder is an uncommon Defect power in Slay the Spire 2. In combat it resolves as: Whenever you Evoke Lightning, deal 6 damage to each enemy hit. It currently underperforms most alternatives, sitting at D tier in our Slay the Spire 2 card rankings.

Across 92 recorded runs, decks running it win 27.2% of the time, comfortably clear of the 18.9% average, by 8.2%. It’s a more selective pick, turning up in just 2.4% of decks that could run it. Defect players keep it in 15.8% of their runs, so it’s a familiar sight in those decks. On average it shows up 1.2 times in the decks that take it.

It performs best next to Energy Surge — together they post a +17.6% swing in win rate. It also has strong chemistry with the relic Blood Vial, which moves its win rate by +27.7%. At 1 energy, it’s upgraded in 30.1% of runs and usually joins the deck around floor 16.

That’s 22 wins, 59 deaths, and 11 abandoned runs with it in the deck. The encounter that most often ends a run carrying it is Kaiser Crab Boss, which closes out 5.4% of its appearances. Read on for Thunder’s complete synergy, class, and threat breakdown to decide whether it earns a slot in your Defect run.

Best Cards to Pair with Thunder

Ranked by win-rate lift, Thunder performs best alongside Energy Surge (+17.6%), Cold Snap (+17.5%), and Genetic Algorithm (+17.0%).

Energy Surge+17.6%5 runsCold Snap+17.5%16 runsGenetic Algorithm+17.0%13 runsHailstorm+17.0%13 runsCreative AI+16.4%12 runsShatter+15.1%14 runs

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

Thunder Win Rate by Class

Thunder is drafted only by the Defect, where it holds a 27.2% win rate across 92 runs.

The Defectappears in 15.8% of its runs (92 tracked)

Best Relics for Thunder

Thunder pairs best with the relics Blood Vial (+27.7%), Red Mask (+21.8%), and Lucky Fysh (+20.8%), ranked by win-rate lift.

Blood Vial+27.7%16 runsRed Mask+21.8%16 runsLucky Fysh+20.8%4 runsJuzu Bracelet+19.1%11 runsPrayer Wheel+18.7%9 runsAnchor???+18.2%7 runs

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

Thunder Card Details

Thunder is an uncommon power costing 1 energy; it’s upgraded in 30.1% of runs and usually picked up by floor 16.

Whenever you Evoke Lightning, deal 6 damage to each enemy hit.

What Ends Runs with Thunder

Thunder’s most common run-enders are Kaiser Crab Boss (5.4%), Knights Elite (5.4%), and Test Subject Boss (4.3%).

• Kaiser Crab Boss5.4% of runs
• Knights Elite5.4% of runs
• Test Subject Boss4.3% of runs
• Queen Boss4.3% of runs
• The Obscura Normal4.3% of runs

See Also

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