I can confirm with Kamekaze's issue. I too have the same issue and that's because of the number of rounds set in the screenpack. If the fight.def has the match set to only one round, it'll affect the HP for the opponents in Survival for some funny reason. If you set the rounds back to its default amount (2), it'll be back to normal.
Kamekaze, check the fight.def and see how many rounds it requires to win a match. If it's set to 1, set it to 2.
Beware the Dark Wolf once more!