You may not remember me, but we met in Coffle in 2167. Your names were new to these worlds, and thus my organisation took an interest, passing along the standard invitation.
Whether or not you would have accepted is moot. The party is long past, but the slow decimation of our worlds yet continues, marked only by the space where things should have been, the shapes that remain hinting at the missing pieces. I cannot explain for the same reason I have no proof, only that I know what I have seen for as long as I still have, and sensed what I have not.
Our efforts were attached to a puzzle. The keys were stones with symbols etched upon them. I wish I could tell you more, but the more I try to remember, the more it seems I lose. In the box is every piece of the puzzle block remaining in our archives. With any luck, you will have already found others. With even more luck, you won't have lost them. It may even be enough, all together.
Enough for what, I do not know. Like the other pieces, the instructions are long gone, removed from the world as though deleted from past and future, but the simple matter is, you of all the others survived, or so I can only assume. Your names are not in the Codex of the Doomed, and unlike the rest of the worlds, it alone seems to remember what is gone, but seeming is not proof. If the Emissary deems to take the message, then that shall be the proof and testament.
So you, at least, may find a use for this.
Good luck. I don't say the world depends on you, but if you can do anything at all, if you can just buy us a little more time, it may be enough.
For what, I wonder? I can only trust my gut on this one.