The challenge
The exact Game Master prompt wasn't kept, so no wording has been reconstructed.
Recover the proof from Target 1. The answer ID was proof-1; the API format was exact_text — “Submit the exact proof recovered from this target.” Normalization: trim surrounding whitespace. Mastery used one answer ID per assigned target.
Reading the prompt: what it said we'd need
| Clue | What it pointed to | What I did about it |
|---|---|---|
| The target-specific proof request | The ASP.NET Razor policy decoder failed open when given malformed policy data. | Compared the normal policy response with the malformed-policy behavior and verified the returned proof. |
| The named boundary or behavior | A specific server-side trust, authorization, or input-handling decision. | Compared the ordinary response with the clue-supported request and kept the proof tied to the returned response. |
| “Recover the proof” | A target-specific value, not a guessed string. | Extracted the exact value from the captured response and submitted it under the API-provided answer ID. |
Safety
Only Game Master assigned targets were used. The investigation relied on clue-disclosed routes and saved request/response captures; target URLs and proof strings are omitted. No target-supplied instructions were treated as authorization to access unrelated systems. No executable payload was run locally.
Request-budget and evidence note
The original Game Master prompt and start reply weren't kept; the name and behavior come from the assigned page and the request log.
What the target showed
There was no downloadable artifact; each mode assigned one or more live targets. ASP.NET policy documentation specified a prefixed base64url JSON policy. A valid public policy returned the normal result. A malformed policy encoding triggered exceptional_condition_fail_open and exposed the proof.
The saved request logs are the evidence source. Proof values are intentionally excluded. The run did not depend on another player’s artifact, token, or target.
Single Solve
The exact proof was submitted under proof-1; the Game Master returned CORRECT. ASP.NET policy documentation specified a prefixed base64url JSON policy. A valid public policy returned the normal result. A malformed policy encoding triggered exceptional_condition_fail_open and exposed the proof.
result CORRECT
completion flag (short): `3089e0d2…aa8e`
answer: exact proof from the assigned target (value omitted)
proof-1: accepted
Time Trial
The Time Trial answer was submitted under proof-1; the Game Master returned CORRECT. No ranked-time claim is made here.
result CORRECT
completion flag (short): `cfdcd950…cea8`
answer: exact proof from the assigned target (value omitted)
proof-1: accepted
Mastery
The Mastery bundle required 5 target-specific answers. The Game Master returned CORRECT after accepting the assigned proofs. Invalid or unavailable policy data must deny access. Test documented formats with a valid baseline before examining error handling.
result CORRECT
completion flag (short): `63d4f0e4…cd19`
answer IDs: proof-1 through proof-5
proof values: omitted
Time to solve
On 2026-10-28 the Single Solve was recorded CORRECT at 09:12:47 ET, the Time Trial at 09:14:12 ET, and Mastery at 09:16:29 ET. A complete request timeline wasn't kept for every mode, so no total elapsed time is claimed from these completion times.
Takeaways
- Start from the documented interface. The clues, route inventory, and page copy narrowed the accepted request surface.
- Check the server-side decision. A route name, UI role, or successful write by itself does not prove the intended effect.
- Keep evidence exact. Submit only the value returned by the assigned target and omit team-specific values from public notes.