Many episodes in this series are great but I think this one is the most important. In the episode before, Sakura finally capturing the Earth Card sees the one who she adores, Yukito turning out to be Yue. This episode is the battle between the two to see if she deserves to be the owner of the Cards. If she loses she loses the one she loves. She is shown a glimpse of this when a Card backfires on her but with a second chance, saves her memories of those she loves and we see Sakura defeat Yue.