Tips on the MN Archive Story Mode Challenge

Okay, go to the second floor and fight there, the cats have a hard time doing their flying swallow attacks there, abuse them with izuna drops. The red ninjas spent most of the time chilling on the bottom trying to throw explosive shurikens through the floor at me. The nice thing is the cats spawn on the bottom level so if you kill them both you can use the essence and slam a UT in the next two cats sorry face as they run up the stairs. Doing this I still had to drop down and mop up about 15 red ninjas after the cats all died though, but dealing with solitary red ninjas is easy enough.

Better yet, do this challenge later... just before you fight Alma.

For some reason, when you do it at this time (I entered the room from the top), the gates to the display room is open. The enemies will not come into the display room. From here, you can use simple strategies to beat the enemies.

Ninjas - Stay just outside the display room until these ninjas come to the 2nd floor. Once they're in front of the display room, run back into the display room. From inside the room, spam jump into Windmill Shuriken. You'll dodge their Incendiary Shurikens while attacking the ninjas. It only takes a few hits from your Windmill Shuriken to kill the ninjas.

Cats - Walk to the tip of the room, enough that the cats will come after you. From the tip of the room, just charge your UT. When a cat comes, kill it with the UT.

Multiple cats - If you have multiple cats on the 2nd floor, run back into the display room so the cats don't attack. From there, run back to the tip of the room and hold block. Wait for a cat to charge at you, block it, then roll backwards. After rolling, just kill the cat with your favorite combo. The cat will either be vulnerable (recovering from its charge), or frantically trying to get out of the room.

If you have multiple cats and a ninja at the same time, stick with the above ninja trick. Since the cats don't have a long range attack, you can just kill the ninjas without worrying about the cats. After killing the ninja, repeat whatever strategy that fits your situation.

You can do this fight without ever using a potion this way.