Pathfinder 2E Rust devil combat

[wicked cool]

Question on the rust devil. Appears the rust devil is more of an enemy behind the scenes. Has anyone used it in an encounter and is it a published adventure

 

[500 Toads]

Haven't run it personally, but one shows up briefly in the first book of the Stolen Fate AP ("The Choosing" being the book); so, depending on your question, maybe look around for threads discussing that one.