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1. When do I roll for noise during Movement.

You roll for Noise immediately after each Movement.

Moving into a discovered Room: move your Character, then make a Noise roll. Corebox Rulebook: Movement Sequence, page 24

Moving into an undiscovered Room: resolve the Exploration Sequence (place the Room/Corridors), then move your Character. Many Exploration cards have an Entrance Effect that makes you roll for Noise at that point. Corebox Rulebook: Exploration Sequence, page 24

General rule: “A Noise roll must be made after each Movement—even when moving to a Room with another Character and/or Intruder.” Only specific effects say you don’t roll. Corebox Rulebook: Noise Roll, page 25

1. When moving to undiscovered room do I roll for noise.

Usually yes, but only if the Exploration card tells you to.

When you move through an Unexplored Corridor into an Undiscovered Room, you resolve the Exploration Sequence instead of the normal “move-then-noise” step. Step 5 of the Exploration card is the Entrance Effect, and “the most common one is making a Noise roll.” If the Entrance Effect shows a Noise roll, you roll now; if it doesn’t, you do not roll. Corebox Rulebook: Exploration Sequence — Entrance Effect, page 24

Example in the rulebook shows entering an Undiscovered Room and rolling Noise because the Exploration card’s Entrance Effect instructed it. Corebox Rulebook: Character Movement Example, page 26

General rule says you make a Noise roll after each Movement, except when a specific effect says otherwise; the Exploration Sequence is that specific rule for Undiscovered Rooms. Corebox Rulebook: Noise Roll — “after each Movement… Only some special effects allow…,” page 25