In my Eberron campaign, the PCs accidentally released a daelkyr and are now trying to put it back. Doing so will involve travelling to various parts of Khorvaire (and possibly beyond) to reassemble the pieces of the artifact use to trap the daelkyr in the first place. They got one piece in a previous adventure (a lens that on its own can be used to see invisible and to focus magic to do more damage to aberrations), and in the latest adventure they found a book that explains what the other pieces are and how to put them together.
However, I have little idea about what exactly those pieces should be. I figure they should involve something made from byeshk (anti-aberration material like cold iron is anti-fey material), and definitely a pretty big khyber shard in which to trap the daelkyr (this one would be a new part rather than finding an old one), but I'm sort of stumped on figuring the others out. So now I turn to you guys in hope of getting me some inspiration.
I'd like there to be at least four other parts, which would make one for each of the others of the five nations (the group is based in Sharn, so I consider the lens the Breland shard - though if I get many ideas, I might go beyond the original concept). I also figure that the Cyre shard should be the last one to get, since the Mournlands is a pretty damn dangerous place to be. Don't feel too constrained about the one per nation thing, I don't mind branching out into other parts of Khorvaire as well (given that most of the other nations came about as splits from the Five, you could easily put the "Karrnath" piece in the Talenta plains or something like that).