Choose your legend and the computer will draw a random rival. You can still click another rival before entering the arena.
Duel's rule system is informed by Melissa Ellen Clow's Natural Math work: finite resources, local agency, explicit limits, persistent consequences, deterministic resolution, and inspectable state transitions.
The arena makes a bounded local-rule system directly playable: visitors can observe how movement constraints, resource pressure, remembered actions, objective ownership, and deterministic opponent policy produce strategic differences.
Eracii-specific characters, movement systems, combat rules, and scoring remain game mechanics. Duel is an applied experiment, not the frozen Natural Math v5 reference implementation.
Status: PLAYABLE APPLIED EXPERIMENT · NATURAL MATH-INFORMED · NOT PART OF THE FROZEN V5 CONFORMANCE RECORD. Rule version: duel-v0.15-source-2026-07-24.