If a player is close enough to an event when it
happens (withing "likely hearing" distance) then if
they later punch the node then they can "collect"
the discovery.
The idea is that if a player hears the sound of
something happening, then they might go and
investigate and discover the thing they thought
they had left there isn't what's there anymore.
In retrospect I may want to combine this with a
limited form of the visual witnessing, just as there
may be events that a player is less likely to touch
in aftermath, or may not be practical to (e.g.
if what's left behind is air)
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