Royal Poison•Relic

Is Royal Poison good in Slay the Spire 2?

Royal Poison is an event relic in Slay the Spire 2. While carried, it does the following: At the start of each combat, lose HP. It’s a reliable mid-tier relic, landing at C tier in our rankings.

Across 48 recorded runs, decks carrying it win 48.9% of the time, comfortably clear of the 13.9% average, by 35.0%. It’s a more situational relic, showing up in just 0.4% of runs. The class that gets the most out of it is the Silent, at a 54.5% win rate. Silent players hold onto it in 0.4% of their runs.

It combos especially well with Ascender's Bane, worth a -1.1% win-rate swing together. Another strong card to run with it is Defend, worth -2.3% to its win rate. On average it’s acquired around floor 41 of a run. Its event rarity shapes how frequently you’ll run into it.

It has 23 run wins against 24 losses in our tracked data. When runs carrying it end, the most frequent culprit is Aeonglass Boss, which closes out 16.7% of them. Read on for Royal Poison’s complete card, class, and threat breakdown before you decide to pick it up.

Pick or Skip: Royal Poison

Royal Poison is taken in 100.0% of its 49 recorded offers, but with 49 runs picking it and 0 passing, neither side has enough decided runs for a win rate yet.

Taken 49 times out of 49 offers.

A win rate is only shown once that side clears the sample floor. Below it you get the run counts and nothing else — a 0% here would be a reporting artefact, not a result.

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.

Best Cards with Royal Poison

Ranked by win-rate lift, the best cards to run with Royal Poison are Ascender's Bane (-1.1%) and Defend (-2.3%).

Ascender's Bane-1.1%23 runsDefend-2.3%16 runs

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

Royal Poison Win Rate by Class

Royal Poison shows up across 2 classes, led by Silent (54.5%) and Ironclad (46.7%) by win rate.

The Silent54.5%11 runsThe Ironclad46.7%16 runs

Royal Poison Details

Royal Poison is an event relic carried in 0.4% of runs and usually picked up around floor 41.

At the start of each combat, lose HP.

What Ends Runs with Royal Poison

Royal Poison’s most common run-enders are Aeonglass Boss (16.7%), Test Subject Boss (10.4%), and Queen Boss (6.3%).

• Aeonglass Boss16.7% of runs
• Test Subject Boss10.4% of runs
• Queen Boss6.3% of runs
• Soul Nexus Elite4.2% of runs

See Also

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