Battle Calculator

Simulate One Column Attack

Select an attacker and the defending front/back cards, then run the battle simulation.

Rules Mode picks which battle logic profile is used. See "Mode Guide" below for exact differences.

Open calculator unit tests

Mode Guide

Current Rules reflects the current intended rules behavior on this site. Historical Rules preserves the older prototype ordering for reference/comparison.

StepHistorical RulesCurrent Rules
Diamond shield vs Club bonus orderClub doubles overflow first, then Diamond absorbs.Diamond absorbs overflow first, then Club doubles what remains.
Heart triggerHeart shield triggers when no card is behind that Heart card.Heart shield triggers when no card is behind that Heart card.
Spade LP bonusDoubles final LP damage.Doubles final LP damage.

If you're unsure: use Current Rules. Use Historical Rules only when checking older examples.

Battle Result

Result output includes stage-by-stage damage totals: attacker base, after front, after back, and final player LP damage.

Run a simulation to see LP damage, suit effects, and which cards survive.

Suit Rules Used By This Calculator

Heart vs Diamond trigger: Diamond triggers when a card is behind it. Heart triggers when no card is behind it.

Example (Historical): 10C into 1D with back 5S: overflow 9 -> Club 18 -> Diamond shields 1 -> 17 hits back.

Example (Current): 10C into 1D with back 5S: overflow 9 -> Diamond shields 1 -> Club 16 -> 16 hits back.

This simulator uses the site's published suit behavior and legacy reference battle math for concrete timing/order.