Alright, you've snagged me, gents. This battle's going to have an interesting arena. It's called the Elements of Change:

Elements of Change
You are suspended high in the air, standing upon a pretty sizable platform. Starting at the end of the first round, two numbers from 1 to 17 will appear for each pokémon. The numbers represent one of the seventeen pokémon types. When the type is selected, both pokémon will have their types change to it, with weaknesses and resistances reflecting their new typing (for instance, Bulbasaur will become a Normal/Fire if 1 and 2 are shown).