The ultimate goal of Chang Jiantao and the others' sneaky outing was originally the Night Fire Spider.
Since Li Pu has fortuitously brought back a significant number of Night Fire Spiders, and they're alive, why should they go out hunting?
Wouldn't buying them be much easier than arduously searching in the deep mountains?
Anyway, for this kind of magic beast, submitting just one living specimen is enough to pass the "Material Collection" end-of-term assessment.
He had heard from his brother that some seniors, unable to complete the assessment at the end of the term and unwilling to fail, would eventually resort to buying materials to pass.
Chang Jiantao thought it's better to be safe than sorry, so he decided to buy a living Night Fire Spider to keep.
If by then he really couldn't complete the end-of-term assessment, he could simply submit it.
In any case, the Night Fire Spider, being a magic beast that poses little threat and is easy to keep, serves as a precaution.
