Prerequisites: Enough scattered bits of this era are referenced that you may as well just watch both seasons beforehand, if you haven't already.

Wish World is actually a fairly decent, if relatively not great, piece of setup. I was actually pretty intrigued by this new world, where skeleton monsters roamed the land, and doubters were locked away. It certainly made for one heck of an opening. However, that's also all it was: setup. Without a satisfying conclusion, that's all it can possibly be (just like last season, and we saw how disastrously that turned out).

Side Note: It's absolutely wild that Dimensions in Time of all times is now canon.