From what I knew, the Mind Realm I entered was pretty much just like mine. With that in mind, I also had a few theories about a very similar phenomenon.
Back when I first met William, he was a lot weaker than he seemed. Even much later on, despite him being a Demon King, just feeling for his energy, I would assume he was no higher than a Grade 30.
I had the same experience with Rachel and even Elise. I couldn't actually feel the extent of their energy. The only thing I could feel was the pressure they just passively emanated, and since those beings had a very terrifying presence, I always just assumed their strength.
Even now, I still didn't know just what kind of Grade Rachel was. That Divine Beast I fought was the same...
Which led me to one simple conclusion.
The way they masked their energy and made themselves appear weaker was through simply sending it into their Mind Realms.
