how does Poltergeist and Corrosive gas react with the oponents Berries?
Interesting if Powder should react to Scorching sand or Beak Blast in future? taking their heat?
I'd also like to know about Poltergeist vs. the Kasib and Jaboca Berries. My guess for the Kasib scenario is, if Poltergeist connects, the Kasib will be consumed, and then Poltergeist will fail at that point. But I have no idea if Jaboca would damage the Poltergeister or what.
Concerning Corrosive Gas, I can't think of any berry, or any other item, that activates upon being removed by a non-attacking move. I think this Gas will just remove the item.
A buff like that to Powder could be fun, if it ever comes back in gen 9. Hopefully Scald would blow up for the same reason then. Also hopefully Scald stops being a TM/TR at that point, and the size of its learnset becomes comparable to Lava Plume and Scorching Sands.