John finally forgave himself for his past mistakes and grew into a stronger, more complex hero when he became the caretaker of the "Mosaic World", a patchwork of communities from multiple planets that had been brought to Oa by an insane Guardian who had invaded John's mind.[6] Although bitter and sullen at his assignment at first, he overcame this and, using his formidable intellect and talent for unconventional thinking, Stewart forged the Mosaic into a new society and eventually became the first mortal Guardian of the Universe, known as the Master Builder. As his reward for this new level of awareness, John was reunited with his late wife, Katma Tui. However, tragedy struck once again and Hal Jordan, possessed by Parallax, destroyed both the Guardians and the Central Power Battery, robbing John of his newfound powers and his resurrected wife.
