>>29899350It can inflict the Poisoned status on Steel and Poison types, but doesn't remove Steel's immunity to Poison type moves. I'm unsure if Steel can still be poisoned by the secondary effect of Poison type moves they're immune to.
Personally I think it's a weird ability to put on a fast mon that's built like a sweeper, especially one that's part Fire and can already deal with Steel types with its STAB. It sure as hell isn't going to be Toxic Stalling anything, so Corrosion seems to be a wasted ability on it.
