The second leg will be more exciting than the first leg, Real Madrid who acts as the host will do everything they can to make a comeback, while Arsenal chooses to play it safe because they want to maintain their victory in the first leg.
I think the second leg will be boring. Since Arsenal won by a big margin of 3-0, there is a big chance that Arsenal will play defensively in the second leg. They will not want to concede goals. Arsenal's defense is already very strong. If this team plays defensively, it will undoubtedly be more difficult for Madrid to score. Madrid will definitely try their best to win. Madrid's attack is also very strong. However, this team is lagging behind because of their weak defense. If they play completely attacking, Madrid's defense will become even weaker and it will be easier for Arsenal to score.