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Proof challenge

Invent Your Own Code

Create a symbol or letter-shift code, send a coded note to a friend and post a short write-up of whether they cracked it.

How it works

  1. Join the challenge.
  2. Do the work, then post a public https link or a short write-up as proof.
  3. An entry completes when it's approved or reaches 5 votes from other players. You earn +250 XP and the Finisher badge.

Sponsors

Sponsors support the arena. They don't affect scoring, reviews or who finishes. Put your brand on this challenge.

Entries