Wyb is a VERY VERY BIG fans of Naruto(漩涡鸣人). Naruto's perseverance and passion attract him a lot, so does Naruto's skill "Kagebunsin no jyutu"(影分身术). Actually, wyb knows more details about "Kagebunsin no jyutu" than most of us. When Naruto makes an new illusion(幻象), his Chakra will divide into two parts A and B, and increase Naruto's weariness value by absolutely value of (A - B).
For example, at first Naruto have 5 Chakra, then he makes an illusion who has 2 Chakra. So he left 3 Chakra, and increase his weariness value by 1 (3 - 2). If he make a new illusion again and give him 2 Chakra, then he only left 1 Chakra and his weariness value changes to 2. Naruto cannot make a new illusion unless his Chakra is bigger than 1. What's more, Naruto's illusion can also use "Kagebunsin no jyutu" and the weariness they gains will also return to Naruto himself.
Now Naruto wants to make as many illusions as he can because Kakashi Sensei wants to teach him a new Ninjyutsu(忍术) and minimum his weariness value.