[RPG] What mundane means can overcome Arcane Lock

dnd-5espells

The arcane lock spell says that a closed door, window, gate, chest, or other entryway "becomes locked". The spell says

it is impassable until it is broken or the spell is dispelled

Okay, impassable is pretty clear, but it's last part of the spell description that confuses me:

the DC to break it or pick any locks on [the object] increases by 10.

Again, the break part is clear: the locked object is off limits unless you can break it with an increased DC. But where does pick any locks fit in? Is the implication that if the door or chest is locked, picking that lock at the increased DC will defeat arcane lock? What if the chest wasn't previously locked? And, if this applies when the chest has a lock but not otherwise, what about the addition of a lock makes it possibly easier to defeat than otherwise? If the object wasn't previously locked, can it now be picked with a DC of 10 (increased from the previous DC of 0)?

Or, is it that one can pick any locks at an increased DC, but the object is still impassable? If so, what is the point of raising the DC? A kind of wizards' ha ha to the rogues out there?

Best Answer

Any normal means by which you'd open a door or window or break an object. It's just harder to do so (though just picking the lock may not be enough).

The last line of this spell handles this

While affected by this spell, the object is more difficult to break or force open; the DC to break it or pick any locks on it increases by 10. (PHB 215)

So if the DC to force open a locked window or door is normally 10, then one under the effect of Arcane Lock is now 20 (and so on and so forth).

Basically, the effect of this spell is to make an easy check a hard one, a medium check a very hard one, and a hard check nearly impossible.

As far as the text "impassible", it seems to mean in this context that the door/window can't be opened by normal means except with the higher DC. It's unclear to me whether or not picking a lock has any effect on this text, though it seems quite clear that forcing the door open is in bounds. I would definitely rule that at the very least picking the lock(s) on the door would ease the DC to force it open (As you're only dealing with the magic and not any physical locks).