Before the run
Main vs beta setup checker
Choose a branch and character, review sourced beta notes, and prepare a solo, co-op or modded setup. This is a manual reference, not a compatibility certificate.
Open tool →A smaller set of useful tools
Free tools for the next Spire run
Use the tool that answers your current question. All run in your browser; none requires a Steam account, save file, subscription, or paid API.
During a decision
Draw probability calculator
Estimate the chance of finding a key card in a shuffled draw pile. Compare a non-target removal or an extra draw, with explicit assumptions.
Open tool →At a reward or shop
Card and relic comparison
Put two main-reference entries side by side. Compare effect, cost, upgrade, rarity, or price before choosing for your current deck.
Open tool →Looking for recent additions? Read the website update log.