The question is.... is it practical to beat the game at that level ?
I've gone through this with Dark Souls... they say you can beat the game at level 1.... and you can.... but what they don't mention is how impractical it is to do so and how unlikely it is to do so if its your first play through.
But the part that really got me was it sort of a Cheap trick... when I looked up how to they beat the game without leveling up.... it turns out they do actually level up.... their Equipment. And then they use Rings and to increase their Stats.
They bamboozled me on a technicality.
Edit:
Is there some long ass In Depth Review of Nioh I can watch to find out exactly how many of this stuff works ?
Or maybe a lets play with some insightful commentary ?
If you want to be able to play the game flawlessly in a first playthrough, forget it.
Abyss mode was not made to people who just got the game, abyss mode is for people that enjoyed the game enough to finish in all difficulties and are looking for extra juicy stuff to do.
The game is technical, is a team ninja game we're talking about here, the game has mechanics for days, and you won't be able to figure them out in the first five minutes, the game gives you the ability to respec your character from the get go, you can try out different builds, playstyles. And you definetly don't need to even get close to the abyss mode to get good at the game.
You can just play through the main missions and you won't be underleveled, i recommend playing the sidemissions because they add a lot to the game (new spirits, more dialogue, more fun).