I didn’t know of other type of oxides that eat into the metal like rust does…

But it’s true that a “rusted crown” implies that it is iron-based, so the cantrip should work!

Yeah… Reading back my comment, it was badly written… I know rust is a type of oxydation, but that’s not what I wrote!

Technically, rust can only occur on iron-heavy metals and alloys. Otherwise it’s just called oxidation.

The difference with “rust” is that rust will eat into the metal and change its shape, while oxydation only changes the surface color and texture.

Edit: yeah… Rust is a specific type of oxydation, it wasn’t really clear from my comment. What I wanted to say is that rust implies the material is iron-based!

We once skipped an entire chapter of “Out of the abyss” by saying “nope!” and running out of the city!

The DM introduced all the factions in the city, we realized they were all conspiring against each other, and they all asked of us to collaborate with them (against the others)… Instead, we stole a ship in the night and sailed away!

Only afterwards the DM told us it means we skipped a full chapter he had worked hard to prepare!