Well.. I expected more from the title.
That being more characters than just six.. That being, there's not much variety in them either. "Oh Deadpool.. Naruto of course.." And I feel there should be more attacks than "lol shooting! Can't dodge wahaha." and "Pow."
Oh, and running into CPU causes damage to your own character, for me at least.
What Viper said is true somewhat, for me at least. The CPU player just runs after one hit. He doesn't disappear for me, but he just runs.