Road to 7: Lostbelt No.3 Section 15 - 3 Node (2/3) Super Recollection Quest
"TA" stands for "Turn Attack", which basically refers to min-turning. For this quest, the minimum turn count required to clear is 2T for Bazett or 3T for other units.
Li Shuwen is a living human in this Lostbelt. This coupled with his man attribute enables Koyanskaya of Light's S2 to provide the full benefit of p100 (powermod 100%) which makes this kind of clear possible.