Fortunately, Roan found Gargantuan Mikrel Worm Blood once they arrived in Glastocen. In fact, he could change it to some other material since Luan's Starlight Body Cultivation Technique wasn't the same as the system's one. Nevertheless, Roan knew this one would work just fine, so he used it.
Luan, unlike Rean and Roan, didn't have Light Element to help out with the pain, so he experienced the full torture of refining his body with the blood. The boy really felt like dying right there and then during the process.
Thankfully, everything went fine, and Luan achieved his First Grade Star Body. With his Nascent Soul Realm cultivation, Luan definitely had the power to fight those an entire realm above himself.
Since the twins had decided to help Luan mature, they decided to stay in Glastocen for a few weeks.
Eventually, the time for the upgrade of the Dimensional Realm was up.
[Dimensional Realm Upgrade to Level 4 completed.]