The graphics were quite fantastic, and the music fit nicely. The general atmosphere was good, though it would have been nice to have some mechanics other than getting keys from chests. Maybe other objects to interact with like finding a torch sconce that opens a hidden passage. That said though it was overall quite good!
A small tip: If you participate in the next jam and want to submit a web build (highly recommended by the way) then Godot 3.x is probably a safer bet. It's a bit sad to not be able to use the latest and greatest but until the web build support is more mature in 4.x we don't have a lot of options!