Halloween at the Portal. The Hollow, a haunted cipher maze, is free to play until 2 November. Enter The Hollow

4 stages · Hard · free account

CLASSIC CIPHER CASCADE

  1. 1 Stage 1: The Shift
  2. 2 Stage 2: The Polyalphabetic Challenge 🔒 opens with stage 1's answer
  3. 3 Stage 3: The Substitution 🔒 opens with stage 2's answer
  4. 4 Stage 4: The Final Coordinates 🔒 opens with stage 3's answer

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Scored puzzles need a free account: your time and hints are tracked by the server, points go on the leaderboard, and each answer unlocks the next stage.

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New here? The five tutorials need no account.