Multiple Missions with the Same Rank

Starting with mission Rank 2-1, there are multiple missions with the same rank. In the Rank 2-1 missions, there are four of them, as shown above. Usually, there are at least one of the missions with the same rank that is very easy to complete and don't require energy, while most of the other missions take just as long or longer than the previous missions that you have completed. You can predict how hard or long a mission is simply by looking at the start button. If there is a button that says "Join a Party" and "Create a Party," then it usually means that that mission will require energy and take time. If not, as shown above, you usually can assume the mission is quick and simple.