Sailor Moon is a pretty skilled fighter, but she’s out of her league against Ash. Ash may just be 10 years old, but he’s a decent fighter when it counts. He can throw a pretty mean punch and he has his Pokemon to back him up. Ash has had many Pokemon over the years, which include Sceptile and Charizard. Those two would be able to overwhelm Sailor Moon with their speed and energy blasts. Ash wins.
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Sailor moon is faster than light and easily destroy galaxies. Many of ash’s Pokemon won’t do much to her as their powers are elemental, and so are Usagi’s as she can use the powers of the other sailor senshi, who are elemental. And this fight wouldn’t even happen as Usagi has the power to look into other’s hearts and see if their good or bad, and I highly doubt that ash, one of the most friendliest characters in anime, will attack a blond teen girl in a princess outfit. This would make for a good fanfic though.
I agree that they would not get into a fight…but if they did, then I believe that Ash would win. I just re-read the manga (Review should be coming within a few weeks) and her feats are very overblown. She can’t move anywhere near that speed in combat and her attacks can barely break buildings. She has some high end feats, but she just can’t really use them in combat and usually plot reasons were involved. By the time she tries to wave her scepter, Ash’s Pikachu would have already taken the win