Dimensions by Kris Aquino ( Books 5-8 ): Dimensions, #5 Mental Universe, #6 Slice and Dice, #7 Do Your Math, #8 Soulless Imposter

Skullcrusher is thrown into a dream realm of another's mind. He then has a philosophical discussion with a transcendent being about the nature of existence and reality and learns transcendence through evolving past selfish narcissism.