Plumeting EoTN rares?

I've noticed while shopping around for a req 9 emerald blade that they have dropped like 50 ecto in value over the past 2 weeks.

While this is great for me as i custo what i buy i was wondering why the sudden drop?

Is this the result of "speed clears" or some solo build?

Seems like some of the others have fallen sharply as well recently.

I dont pve and was wondering why this is, thx.

When a particular dungeon or dungeon boss becomes the Zbounty, everyone who can gets run for each and every character they can. So there is a rush to that dungeon and so the chances are a lot more of that rare item that dungeon drops will get had. Sudden influx of an item causes that item's price to drop for a time.

The more that are available the less it is rare, therefore the value becomes less.

You can blame speed clears mainly for this.