Run Companion
Real-time card pick recommendations based on your deck
How does the Run Companion work?
The Run Companion helps you decide which card to pick during your Slay the Spire 2 run. It scores each candidate card based on community win rate data, how well it fits your current deck's archetype, and synergy with your existing cards.
Three ways to use it:
In-game mod (best)
Install the Card Rewards Helper mod on Nexus. Same scoring and recommendations as this page, rendered directly in-game on every card reward screen — no window switching, no save file paste. Recommended for active play.
Auto-sync with rusty-sts
Install rusty-sts, our desktop companion app. It watches your save file and automatically syncs your current run to this page every few seconds. Your deck, floor, and ascension update in real-time as you play — just keep this page open and enter card rewards when you need help deciding.
Manual mode
Select your character, add your cards manually or import your current_run.save file, then enter the card reward options to get recommendations.
Score breakdown:
- Score (30%) — pre-computed card strength from win rate delta + ELO. A10 data in Pro mode
- Synergy (40%) — win rate when paired with non-starter cards in your deck
- Copies (17%) — whether adding another copy helps or hurts win rate
- Upgrade (13%) — bonus for picking the upgraded version
Data source:
Recommendations are scored on solo runs from the latest game version. When the character + ascension cohort doesn't have enough runs on the current patch yet, the pool is backfilled with the most recent runs from previous patches (up to 1000 total) so you still get meaningful stats on fresh patch days.
Character
Where is my save file?
Your current run save file is located at:
C:\Users\<YourUsername>\AppData\Roaming\SlayTheSpire2\steam\<SteamID>\profile1\saves\current_run.save On macOS/Linux, look for SlayTheSpire2/.../saves/current_run.save in your app data directory.
Choose your character above, or import a .save file to load your current run.
