Arrays used the energy of the universe to power themselves, but drawing the character required the user's own spiritual energy. Back when Lex started out, he had two great obstacles - his drawing speed, since each character needed to be perfect, and his energy reserves.
Neither of those had been a problem for Lex for a long time, yet as he began to draw the character from the Book of Changes, he found that the energy was practically pouring out of him as he drew it.
"Yeah, these are probably super normal characters," Lex said as he completed the character. Fortunately, he didn't need to draw an entire array just yet - simply identifying the correct character was enough.
After a long time of observing and monitoring the situation, Lex eventually discovered that the wrongness seemed to have a certain flavor to it. As it happened, the description of the characters in the Book of Changes described the perfect character to correct it.
