Starfire's exploration of the underground ruins wasn't that of the sandbar's Titan's Relics. This was also the location Li Yao had chosen for Starfire members to level up.
Starfire now had a considerable number of members, plus those from the sub-guild. Developing these ruins shouldn't be a problem.
Adding to that, the special items Li Yao had prepared in advance were more than enough for Starfire to successfully develop the site.
In fact, it wasn't the experience from that location that Li Yao was interested in, but rather he had an ulterior motive. He had influenced Sister Li and the others to make this decision without revealing his true thoughts to them.
