I have been playing on skyblock for quite some time now and the #1 question that is asked 5+ times a day is "Why doesn't my slime spawner work?" So I have decided to make a simple tutorial for people to read. This is what is required for your slime spawners to work. Slimes only spawn at a level below Y=40. What does that mean? Press F3 (some of you may need to use FN+F3) and it will bring up a lot of information. On this list look for the X,Y,Z coordinates. The middle number (Y) is the number that needs to below 40. So you will need to build down to below 40, most of us build down by using a water elevator if you don't have fly, to level 1 (Y=1). Build down by placing blocks under each other to form a column down to level 1. Now that you have made it to what ever level you decide to stop at (Below Y=40) start building your platform. I started with a 100x100 platform because this gave me the maximum number of "chunks" to look for slimes in. Slimes will only spawn in a "Slime Chunk". A chunk is a 16x16 block square which can be seen by pressing f3+g (some of you may need to use FN+F3+g). Doing this will bring up grid lines that have different color lines. The YELLOW lines are the chunks. Now that you can see the chunks, take your slime spawner and place it in the middle of one of the chunks (in the YELLOW lines). If a slime spawns that is a slime chunk, the entire 16x16 area is the slime chunk. Mark this with a block of you choice and pick up the spawner. If you are NOT RANKED you will need a pick with SILK TOUCH on it to pick up the spawner, RANKS do not need a silk touch. Now move on from chunk to chunk and repeat the process. If a slime spawns it is a chunk (a place where you can build your slime generator), if slimes do not spawn it is not a chunk. That is how you find and identify where you can build a slime generator. I hope this helps. Just remember if you are placing your slime spawners on your starting island level they won't work. Good luck to you.