First mentioned in chapter 1670, when Shi Feng discovered that the Realms of Truth were mentioned as part of God's Domain lore.
The Realms of Truth focuses on improving the person's control over their body and utilizing the environment. In the game, it will help increase the combat power of the player, allowing them to perform actions and exhibit power beyond their usual state. Unlike the Realms of Refinement, the Realms of Truth focused on exerting the maximum potential of one's body, rather than the five senses. Hence, even when controlling summoned creatures, they are able to exert the same performance their controller has achieved in the Realms of Truth.
The Realm of Truths is a lesser known state of being, therefore most superpowers do not know about it or have training programs to train people. Hence, there are very few people who are able to enter this state. So far, Endless Scars has come across it and labelled it as 'Spiritualization Realm'.
So far the stages we know of are:
The difficulty of progressing in the Realms of Truth can be seen from the following extract: "One could not simply reach the Ascension Realm by understanding the realm's philosophy. They would also need to temper themselves and gain the experience of countless life-or-death battles to execute the proper physical response."