How does Corrosion work with Magic Coat?

Question

If a Steel- or Poison-type Pokemon used Toxic/Poison Power/Poison Gas/Toxic Thread on a Pokemon with the ability Corrosion that just used Magic Coat, what would happen? So say a Skarmory/Muk used Toxic against a Smeargle that was given the ability Corrosion and that just used Magic Coat. Would the Skarmory/Muk be poisoned or not?

As a side question, is there any way to give a Pokemon Steel/Poison typing through moves or abilities? If so, how would the Corrosion/Magic Coat scenario unfold?

Thanks

Answer 1

The steel or poison Pokemon would get poisoned.
source
Currently, there are no ways to legally get a steel poison Pokemon. There are no Pokemon or forms of Pokemon that are steel poison type. The only moves and abilities that can change a Pokemon's type AND leave it with two types are reflect type (which requires a poison steel Pokemon to already exist), trick-or-treat (which can only add ghost type), forest's curse (which can only add grass type), burn up, and roost (which can only remove types).

Comments

To clarify, Burn Up removes a Pokémon's Fire-typing (Only the Cyndaquil line and Moltres  can learn this through level-up; only Growlithe and Arncanine can have access to this move as an Egg Move). Roost removes a Pokémon's Flying-typing (Although it is TM19, mostly Flying-types can learn this move either through TM or level-up).

Also, the only Pokémon that can learn Trick-or-Treat is the Pumpkaboo line, whereas the only Pokémon that can learn Forest's Curse is the Phantump line.

Reflect Type can be learnt by Tentacruel, Staryu, Mew, and Latias through level-up. The Gastly line, Omanyte line, Castform, and Stunfisk can learn this move as an Egg Move.