W:DH for Waterdeep: Dragon Heist.
In general I like the book on skimming.
The Nimblewright on p.212 is quite tasty.
The fluff + adventure back in the 40s and 50s,
provide some details. Lantan Wizard dude
crafted it, and left it (?) with a cleric org.
It's able to craft another one of itself.
I'll guesstimate it's a Rare magic item.
This back implies some interesting things about crafting itself.
I want one.
I want one more than I want some Fighters or Barbs, or most Rangers.