HeavyG said:If you polymorph into Pikachu (or a blue dragon, or anything widely known to be immune to lightning), the blue dragon will probably not waste its breath weapon on you. It doesn't know you're not really immune, see ?
Well done that man! It would be best if the dragon didn't see you change, but if it sees something that it knows can't harmed by electricity, it probably won't bother breathing electricity at it.
The trick is to pick something that is well-known for it's resistance to lightning.