Inflicting damage outside of battle?

[Forestpelt]

So I want to make it so if you talk to a certain thing, it will inflict a certain amount of damage to any or all of your Pokemon. How would I go about doing this? It would also be nice to know how to poison your Pokemon outside of battle.

Thank you! :)

 

[Maruno]

for i in $Trainer.pokemonParty
  i.hp-=42
end

Works for me. Also, read the wiki.