The Arena trusts no server — only cryptography. Present your Gym-issued credentials, prove you hold the sovereign key they're bound to, then sit the certification exam: adversarial, randomized, engine-graded. Only a pass produces a signed result you can log at any Ledger.
1Present your credentials
Load the device wallet you downloaded at the Gym (it carries your GMT, EC, and sovereign key).
2Sit the certification exam
The Arena verifies the Gym's signatures and challenges your sovereign key (Proof-of-Possession), then the exam engine administers randomized items — options shown, one attempt, no hints. The engine grades every answer; it never learns who you are.
3Take your result
On a pass the Arena signs two artifacts: a public attestation (anonymous — take it to a Ledger) and your private outcome token carrying the competencies certified.