Kongjin-dan was traditionally a royal court tonic and is highly effective for exam students: ① severe fatigue/exhaustion (key ingredients deer antler, ginseng restore vitality), ② concentration/memory improvement (musk activates brain function), ③ stress relief, ④ post-illness recovery, ⑤ critical support during exam season. Take 1 ball morning, with effects felt 2–4 weeks. Taken before exams, fatigue/concentration improvement is reported.