The knock spell's description reads:
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 you choose a target that is held shut with arcane lock, that spell is suppressed for 10 minutes, during which time the target can be opened and shut normally.
When you cast the spell, a loud knock, audible from as far away as 300 feet, emanates from the target object.
As far as I see it, the description of the knock spell describes 4 things:
- What the knock spell can target.
- What happens if the knock spell targets something locked by a mundane lock, or is stuck or barred.
- What happens if the locking mechanism is specifically the spell arcane lock.
- The spell creates noise.
Valid spell targets include magical locks. But it doesn't seem the spell says what it does when such a target is selected (except for create a loud knock sound). This is the case, unless a magical lock is considered 'stuck' in which it is according to the spell the lock would be unstucked.
However, the spell says what it does to stuck things where it specifies what happens to a target that is held shut by a mundane lock, or stuck or barred. If magical locks were considered stuck, there wouldn't have been any need to specifically say what happens to a mundane lock, because it would apply to non-mundane locks too.
I originally asked this question here, but the question unfortunately got edited into a different question. The answer there addresses the question it got edited to. So I feel it is appropriate readdress the main issue in a new thread. For this reason, I don't think this is a duplicate question, even though I copied the majority of the content of this question from that thread.