STS2 calculator suite

Every tool answers a concrete in-run question. Pick by intent — not by hype keywords.

💀 Lethal math

Necrobinder Soul Calculator

Quick single-card soul and doom damage checks.

🎴 Deck thinning

Draw Probability Calculator

Hypergeometric odds to see key cards in your next draw.

⚒️ Scaling EV

Regent Forge Estimator

Compare simplified forge and star power scaling scenarios.

⚡ Multiplayer

Co-op Synergy Checker

Review curated two-character pairings and role coverage.

Not sure where to start?

First-run guide — when tools matter vs when they distract
FAQ — how we differ from wiki sites
Mechanics — keywords and systems notes

STS2Calc is an independent fan-made tools site and is not affiliated with Mega Crit or the official Slay the Spire 2 wiki. Game systems may change in Early Access.