They explained it well enough so I'll not be adding too much unless you guys have a question. This fight will use the normal rules as linked to but won't be as strict, allowing you guys to get away with a bit more extra stuff you wouldn't in a serious competition such as getting unusually lucky and of course the whole business of making up powers on the fly being possible (which I have to stress is highly frowned upon in most arena battles, so also be sure to see if you need to post character sheets first in other arena battles and don't deviate from their listed powers). 

I'll post the thread for this today unless something horribly unexpected happens.