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

3 stages · Hard · Premium

SEQUENCE LABYRINTH

📜 Briefing
The machines build their simulations on numbers. Find the next term in each sequence to walk the labyrinth.
  1. 1 Layer 1: Fibonacci Mystery
  2. 2 Layer 2: Mersenne Primes 🔒 opens with stage 1's answer
  3. 3 Layer 3: Cubic Formula 🔒 opens with stage 2's answer

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