This is a pretty good idea for people who want to do Skyblock for the long-term. Basically, Skyblock can be split up into three segments, EASY, MEDIUM and HARD. Upon choosing the difficulty, the different challenges will be altered. Easy would be less resources to get, but a lesser reward, medium would be challenges would be the original, and hard would be challenges with higher rewards for higher amounts of stuff. When you do that, you have a choice to either restart your island, or to carry on (which can be later accessed if you'd like). If completed all three, you will get some type of reward.