Lu Zhiyu entered the painting space and immediately discovered that the very first queen insect had died. It was jointly attacked by a few other queen insects that appeared later on, dragged out from its nest, and died a horrible death.
It was precisely at the moment the queen insect died that the measure of the Source Form in Lu Zhiyu's brain increased. Lu Zhiyu then brought his consciousness into the painting space and gradually discovered that the Source Form's increase did not only occur when the queen insect died. In fact, every time a living thing died, the measure of the Source Form would increase subtly.
He did notice that there was a great difference between an ordinary insect and a queen insect. As the changes were minimal for ordinary insects, Lu Zhiyu had not noticed the difference before. It was only when the queen insect died, and the measure shot up, that this great difference caught his attention.