Knock: resolve one lock and account for the noise

SRD 5.2.1 · Spell decisions

Before casting

At the table

1. Choose a visible object within range that contains a mundane or magical means preventing access.
2. A mundane lock, stuck closure or bar can be opened by the spell; on an object with multiple locks, only one lock is unlocked.
3. Arcane Lock is suppressed for ten minutes, and a loud knock audible up to 300 feet emanates from the target.

Example decision

A visible chest has three separate mundane locks. One Knock casting targets the chest. How many of its locks does that casting unlock?

One of the three locks.

The spell explicitly limits an object with multiple locks to one unlocked lock. The remaining locks still need a solution before access is available. The loud knock is an additional consequence, so a plan that depends on secrecy must account for nearby listeners rather than assuming magical entry is quiet.

Watch for this mistake

For Arcane Lock, the text says suppressed for ten minutes, not permanently dispelled. Keep the access window and the object’s other barriers visible when describing the result.

Ask the table

Which barrier is being removed, what remains, and who might hear the knock?

Source spell

Level 2 Transmutation (Bard, Sorcerer, Wizard) Casting Time: Action Range: 60 feet Components: V Duration: Instantaneous Choose an object that you can see within range. The object can be a door, a box, a chest, a set of manacles, a padlock, or another object that contains a mundane or magical means that prevents access. A target that is held shut by a mundane lock or that is stuck or barred becomes unlocked, unstuck, or unbarred. If the object has multiple locks, only one of them is unlocked. If the target is held shut by Arcane Lock, that spell is suppressed for 10 minutes, during which time the target can be opened and closed. When you cast the spell, a loud knock, audible up to 300 feet away, emanates from the target.

Source: SRD 5.2.1, 143–144. Online guide.