Last time in the Frost Fall Mountain Range, after the Snow Lynx had attacked, Lin Su had readied such an iron staff in his Space Ring.
With a weapon, he could utilize his strength from the Body Refining Realm more effectively, but having lost the memories of his original self, he had no idea how to employ swordsmanship or knife technique; after much thought, he decided the iron staff, with its minimal usage threshold and great length, was the most suitable weapon for him.
The so-called "an inch longer, an inch stronger" held true; it was indeed the most suitable weapon for him.
Previously, when facing the attack of the flying leaves and Vine Whips, holding a staff wasn't enough to fend off so many attacks, and since the iron staff was quite heavy, carrying it would inevitably slow down his speed, which is why Lin Su didn't use it, and against the Ice Armor Scorpion afterward, the staff was useless.
Only now, Lin Su's preparation finally came into play.