Signal BoostSkill
The next Power you play is played an additional time.
Is Signal Boost good in Slay the Spire 2?
Signal Boost is a rare Defect skill in Slay the Spire 2. In combat it resolves as: The next Power you play is played an additional time. It ranks among the strongest cards its class can draft right now, earning a spot at B tier in our Slay the Spire 2 card tier list.
Across 4 recorded runs, decks running it win 25.0% of the time, comfortably clear of the 12.6% average, by 12.4%. It’s a more selective pick, turning up in just 0.8% of decks that could run it. Defect players keep it in 14.3% of their runs, so it’s a familiar sight in those decks. On average it shows up 1.5 times in the decks that take it.
It performs best next to Hotfix — together they post a +8.3% swing in win rate. It also has strong chemistry with the relic Cracked Core, which moves its win rate by 0.0%. At 1 energy, it’s upgraded in 33.3% of runs and usually joins the deck around floor 7.
Upgraded, it gains -1 EnergyCost, which is why so many decks invest a rest-site upgrade in it. That’s 1 wins, 3 deaths, and 0 abandoned runs with it in the deck. The encounter that most often ends a run carrying it is Kaiser Crab Boss, which closes out 50.0% of its appearances. Read on for Signal Boost’s complete synergy, class, and threat breakdown to decide whether it earns a slot in your Defect run.
Signal Boost Win Rate & Pick Rate
Signal Boost’s 25.0% win rate clears the 12.6% all-deck average by 12.4%, the gap charted below.
Run Outcomes with Signal Boost
Signal Boost has 1 wins and 3 losses over 4 tracked runs (25.0% won); abandoned runs count as losses.
- Wins 25.0%
- Losses 75.0%
Best Cards to Pair with Signal Boost
Ranked by win-rate lift, Signal Boost performs best alongside Hotfix (+8.3%), Subroutine (+8.3%), and Defend (-25.0%).
Based on small co-occurring samples — treat these as early signals, not final verdicts.
Signal Boost Win Rate by Class
Signal Boost is drafted only by the Defect, where it holds a 25.0% win rate across 4 runs.
The Defectappears in 14.3% of its runs (4 tracked)Best Relics for Signal Boost
Signal Boost pairs best with the relics Cracked Core (0.0%), ranked by win-rate lift.
Based on small co-occurring samples — treat these as early signals, not final verdicts.
Signal Boost Card Details
Signal Boost is a rare skill costing 1 energy; it’s upgraded in 33.3% of runs and usually picked up by floor 7.
The next Power you play is played an additional time.
Upgrade: -1 EnergyCost
What Ends Runs with Signal Boost
Signal Boost’s most common run-enders are Kaiser Crab Boss (50.0%).
- Kaiser Crab Boss50.0% of runs
Help us maintain accuracy! If you notice incorrect stats, missing data, or any issues, your feedback directly improves the quality of our data for the entire community.
Signal Boost – Frequently Asked Questions
Is Signal Boost good in Slay the Spire 2?
Across 4 tracked runs, Signal Boost has a 25.0% win rate — +12.4% above the average deck. Win rate reflects how often runs that include the card end in victory.
What does Signal Boost do in Slay the Spire 2?
Signal Boost costs 1 energy. The next Power you play is played an additional time.
What class is Signal Boost in Slay the Spire 2?
Signal Boost is a Rare Defect Skill.
Is Signal Boost worth upgrading in Slay the Spire 2?
Players upgrade Signal Boost in 33.3% of runs. Upgrading it grants -1 EnergyCost.
What is the best relic for Signal Boost?
In tracked runs, Signal Boost has performed best alongside Cracked Core, which lifts its win rate by 0.0% over 4 runs together.
See Also
Compare Signal Boost with the rest of the best Slay the Spire 2 cards, relics, and classes below.