At a certain point in the game, you really don't need these AR codes, as this is essentially a level -2 run with no partners (5HP, 0BP, 0FP), and eventually most enemies do 5 damage or more. All the unranked partners don't add too much other than a few extra hits when they can't use FP. And my personal feel is that if you take that much away from Mario's battle capabilities, it's literally nothing but repeated superguarding that makes it possible. Not that it isn't challenging, it certainly is, but it's a type of challenge I believe one can't approach in a clever way or play smart to complete, just very very reliable and nimble fingers. (Compared to the level 0 run, where partner selection, item distribution, and battle strategy all still play a major role, and 100% accurate superguarding isn't required.)

It's like playing Fire Emblem Awakening on Lunatic+ without using Fredrick.

As a side note, the Mario and Luigi games allow for "no hit" runs much better than Paper Mario games do, imo.

The moment you take off that 0BP code, Mega Rush can be used essentially without any limits like Power Rush can in a Danger Mario setup. Combine some Close Calls and Luck Badges with a supply of Life Shroom for when the Lucky fails, and you got a potent glass cannon Mario.

Does that Zero Max Partner HP work on more than Goombella? If so, I may want to keep that code in mind.