Noxious Fumes•Power

Is Noxious Fumes good in Slay the Spire 2?

Noxious Fumes is an uncommon Silent power in Slay the Spire 2. In combat it resolves as: At the start of your turn, apply Poison to ALL enemies. It currently underperforms most alternatives, sitting at D tier in our Slay the Spire 2 card rankings.

Across 534 recorded runs, decks running it win 23.7% of the time, comfortably clear of the 13.9% average, by 9.7%. It’s a more selective pick, turning up in just 4.6% of decks that could run it. Taken in 32.3% of its offers, it still trails on the pick-versus-skip split: 24.5% for runs that took it against 29.8% for runs that left it, a -5.2% pick lift over 408 decided runs. Silent players keep it in 18.0% of their runs, so it’s a familiar sight in those decks. On average it shows up 1.3 times in the decks that take it.

It performs best next to Tactician — together they post a +20.3% swing in win rate. It also has strong chemistry with the relic Fragrant Mushroom, which moves its win rate by +31.7%. At 1 energy, it’s upgraded in 41.7% of runs and usually joins the deck around floor 14.

That’s 126 wins, 406 deaths, and 2 abandoned runs with it in the deck. The encounter that most often ends a run carrying it is Kaiser Crab Boss, which closes out 5.2% of its appearances. Read on for Noxious Fumes’s complete synergy, class, and threat breakdown to decide whether it earns a slot in your Silent run.

Pick or Skip: Noxious Fumes

Out of 1490 recorded offers Noxious Fumes is taken 32.3% of the time, and taking it is worth -5.2% in pick lift — 24.5% for runs that picked it against 29.8% for runs that skipped, across 408 decided runs.

Taken 481 times out of 1490 offers.

Pick rate when offered counts offers, not runs: out of every time the game put this in front of a player, how often it was taken. It is not the same number as the share of runs that end up containing it.

Pick lift is the sample-adjusted gap between runs that took the option and runs that passed on it. It is the fair way to rank choices, because raw win rates put the smallest samples on top.

When to Pick Up Noxious Fumes

Noxious Fumes is strongest when it joins the deck in Act 3, where runs win 58.5% across 42 runs — one of 4 recorded pickup windows.

Win rate of runs by the act Noxious Fumes entered the deck. Acts that have not reached the sample floor show their run count only.

Best Cards to Pair with Noxious Fumes

Ranked by win-rate lift, Noxious Fumes performs best alongside Tactician (+20.3%), Mad Science (+20.1%), and Decay (+20.0%).

Tactician+20.3%91 runsMad Science+20.1%32 runsDecay+20.0%16 runsPanache+19.4%22 runsMalaise+18.3%31 runsAdrenaline+17.9%88 runs

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

Noxious Fumes Win Rate by Class

Noxious Fumes is drafted only by the Silent, where it holds a 23.4% win rate across 523 runs.

The Silentappears in 18.0% of its runs (523 tracked)

Best Relics for Noxious Fumes

Noxious Fumes pairs best with the relics Fragrant Mushroom (+31.7%), Sai (+29.8%), and Bellows (+29.3%), ranked by win-rate lift.

Fragrant Mushroom+31.7%25 runsSai+29.8%15 runsBellows+29.3%20 runsPantograph+26.1%42 runsGame Piece+25.8%18 runsMiniature Cannon+24.8%33 runs

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

Noxious Fumes Card Details

Noxious Fumes is an uncommon power costing 1 energy; it’s upgraded in 41.7% of runs and usually picked up by floor 14.

At the start of your turn, apply Poison to ALL enemies.

What Ends Runs with Noxious Fumes

Noxious Fumes’s most common run-enders are Kaiser Crab Boss (5.2%), Aeonglass Boss (4.9%), and Test Subject Boss (4.9%).

• Kaiser Crab Boss5.2% of runs
• Aeonglass Boss4.9% of runs
• Test Subject Boss4.9% of runs
• Knowledge Demon Boss4.5% of runs
• Decimillipede Elite4.1% of runs

See Also

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