The Basics:
Long ago, there were well-kept secret chests in Dereth that continually spawned awesome loot. These Uber Chests were utterly camped by a select few, who were raking in the good stuff.
They result of this was the turning off of all Uber chests. Instead, Special Keys would be dropped only from high-level monsters, allowing access to the well-guarded Uber chests.
And the Strudy Iron Key was born.
Gettting Keys:
Unlike Motes, shards, and Slivers, Keys are dropped by a variety of baddies. The drop rate is beteween 1 in 20 and 1 in 100
Some days, it is 1 in 10, others, I kill 100s without finding one -- literally.
My advice is -- when the keys are flowing, hunt them vigorously.
And, when the keys are not flowing, you may choose to hunt something else.
You can always buy/trade for keys as well. Some people will scoff at you for trying to buy keys... but - I did it.... through overpaying for them. You can buy keys for between 50-100k. People can't resist. See the Money making section if you prefer this route.
Using Keys:
I can't really describe much here - becuase I have had BAD luck with kys ....
Let me know if you have better luck, and WHERE :)