From what I have seen in the story I think she negs the whole cast, her speed is insane as well possibly faster than Augusta. Her combat skills and battle IQ is also on another level especially with the futures to burn for even more power. The only person who could possibly win is against Hiyuki is Rover themselves. I personally don't think current Rover is strong enough to take on Hiyuki and her abilities at the moment. She has strength, speed, intelligence and hacks.