The rules of the tournament of course would need to be explained.  Helena shook her head in mild amusement as she looked the merc in the eyes, unaffected by how cold and deadly she appeared with that scythe of hers, and who knew what else she had in her possession, much like Ryu and his Ninpo magics, or Yuna and her Aeons or Giselle and Tyger's own mystical abilities.  "Killing your opponent is not allowed if they are like you in the sense they are sentient beings.  In all of the years of DOA, we've had seriously injured people perhaps, but never killed, not in our sanctioned matches anyway.  Knockouts are the only way to win your fights, but any means to accomplish this is most definitely allowed this time.  In the past it was fist against fist, no weapons besides the human one was allowed.  Because of the different races among us, that rule has been tossed, and if a death is unavoidable, then we will deal with it as best as we can."  Helena answered, on death's door herself as she looked to Ryu and sighed as she unbuckled herself a moment before the sign came on that it was ok to do so.  "Feel free to move about the plane but stay out of the way of anyone that works for me please.  If an emergency should happen, follow the instructions given out as best as you can because it could very well save your life."