Gunk Up Attack

Is Gunk Up good in Slay the Spire 2?

In Slay the Spire 2, Gunk Up is a common attack from the Defect card pool. Its effect: Deal 4 damage times. Add a Slimed into your Discard Pile. The data flags it as a weaker pick, settling at D tier — usually one to pass on unless your deck specifically wants it.

Over 755 tracked runs its win rate sits at 12.6%, 1.2% short of the 13.8% all-deck baseline. It sees niche play, included in only 3.6% of eligible runs. Offer data argues the other way: taken 20.0% of the time it is shown, runs that picked it win 11.8% against 16.7% for runs that passed — a -4.8% pick lift across 634 decided runs. Within Defect runs it’s drafted 16.3% of the time, making it a regular part of that class’s decks. Decks that include it run about 1.4 copies on average.

Its standout pairing so far is Modded, which lifts its win rate by +26.1% when the two share a deck. On the relic side, Runic Capacitor is its standout companion, worth a +24.0% win-rate swing alongside it. It costs 1 energy, gets upgraded 22.5% of the time, and tends to be picked up near floor 11.

Upgrading the card adds +1 Damage to its stat line. Of the runs that drafted it, 94 ended in victory against 651 deaths and 10 abandons. Its most common run-ender is Kaiser Crab Boss, finishing 6.0% of the runs it shows up in. See the synergies, class split, and threats below for the full picture of where Gunk Up fits a Defect deck.

Pick or Skip: Gunk Up

Players take Gunk Up in 20.0% of the 4091 offers it appears in; those runs win 11.8% against 16.7% for runs that passed, a pick lift of -4.8% over 634 decided runs.

Taken 818 times out of 4091 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 Gunk Up

Of the 4 pickup windows recorded for Gunk Up, Act 3 is the best: 40.0% across 35 runs.

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

Best Cards to Pair with Gunk Up

Gunk Up’s strongest card pairings so far are Modded (+26.1%), Shadow Shield (+23.1%), and Decay (+23.0%), each shown with the win-rate lift it adds.

Modded+26.1%50 runsShadow Shield+23.1%44 runsDecay+23.0%16 runsSupercritical+21.0%77 runsIteration+20.6%111 runsFusion+19.9%43 runs

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

Gunk Up Win Rate by Class

Exclusive to the Defect, Gunk Up posts a 12.4% win rate over 746 tracked runs.

The Defectappears in 16.3% of its runs (746 tracked)

Best Relics for Gunk Up

The relics that swing Gunk Up’s win rate the most are Runic Capacitor (+24.0%), Power Cell (+23.0%), and Tiny Mailbox (+21.2%), with each lift shown.

Runic Capacitor+24.0%18 runsPower Cell+23.0%16 runsTiny Mailbox+21.2%44 runsMeat on the Bone+20.5%27 runsPetrified Toad+20.1%62 runsBag of Preparation+19.6%87 runs

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

Gunk Up Card Details

A 1-energy common attack, Gunk Up is upgraded 22.5% of the time and tends to enter the deck around floor 11.

Deal 4 damage times. Add a Slimed into your Discard Pile.

Upgrade: +1 Damage

What Ends Runs with Gunk Up

Runs holding Gunk Up end most often against Kaiser Crab Boss (6.0%), The Insatiable Boss (5.3%), and Knowledge Demon Boss (4.8%) — the share of its runs each accounts for is shown.

• Kaiser Crab Boss6.0% of runs
• The Insatiable Boss5.3% of runs
• Knowledge Demon Boss4.8% of runs
• Infested Prisms Elite4.5% of runs
• Lagavulin Matriarch Boss4.0% of runs

See Also

Keep exploring Slay the Spire 2 tier lists and stats below.