Subroutine•Power

Is Subroutine good in Slay the Spire 2?

Subroutine is an uncommon Defect power in Slay the Spire 2. In combat it resolves as: Whenever you play a Power, gain -cost. It currently underperforms most alternatives, sitting at D tier in our Slay the Spire 2 card rankings.

Across 9 recorded runs, decks running it win 11.1% of the time, trailing the 12.6% average by 1.5%. It’s a more selective pick, turning up in just 1.7% of decks that could run it. Defect players keep it in 32.1% of their runs, so it’s a familiar sight in those decks. On average it shows up 1.9 times in the decks that take it.

It performs best next to Storm — together they post a +22.2% swing in win rate. It also has strong chemistry with the relic Blood Vial, which moves its win rate by +22.2%. At 1 energy, it’s upgraded in 11.8% of runs and usually joins the deck around floor 15.

Upgraded, it gains -1 EnergyCost, which is why so many decks invest a rest-site upgrade in it. That’s 1 wins, 8 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 22.2% of its appearances. Read on for Subroutine’s complete synergy, class, and threat breakdown to decide whether it earns a slot in your Defect run.

Best Cards to Pair with Subroutine

Ranked by win-rate lift, Subroutine performs best alongside Storm (+22.2%), Sunder (+22.2%), and FTL (+22.2%).

Storm+22.2%3 runsSunder+22.2%3 runsFTL+22.2%3 runsSignal Boost+22.2%3 runsDouble Energy+22.2%3 runsSynchronize+22.2%3 runs

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

Subroutine Win Rate by Class

Subroutine is drafted only by the Defect, where it holds a 11.1% win rate across 9 runs.

The Defectappears in 32.1% of its runs (9 tracked)

Best Relics for Subroutine

Subroutine pairs best with the relics Blood Vial (+22.2%), Centennial Puzzle (+22.2%), and Meal Ticket (+22.2%), ranked by win-rate lift.

Blood Vial+22.2%3 runsCentennial Puzzle+22.2%3 runsMeal Ticket+22.2%3 runsWhetstone+22.2%3 runsCracked Core0.0%9 runsGorget-11.1%3 runs

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

Subroutine Card Details

Subroutine is an uncommon power costing 1 energy; it’s upgraded in 11.8% of runs and usually picked up by floor 15.

Whenever you play a Power, gain -cost.

Upgrade: -1 EnergyCost

What Ends Runs with Subroutine

Subroutine’s most common run-enders are Kaiser Crab Boss (22.2%).

• Kaiser Crab Boss22.2% of runs

See Also

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