So I've been playing skyblock for a while now, and I have made a very large platform (still a work in progress) using cobble half slabs and I get twice as many blocks to use to cover ground. However, I have made sure that it is an even Y coordinate (I mean its not 62.5 or something) and no mobs will spawn. I am in a desert/river biome and most of the platform is desert, but no mobs will spawn, and I want to make a classic mob grinder without the struggle of earning enough iron/diamonds to buy a spawner. Any help? Maybe I'm just stupid and didn't think that mob spawning could be disabled or I'm too close/far.

 

i'm new to the server and not sure about spawning here but I do know mobs do not spawn on half slabs unless there is a mod for that.

 

Mobs do not naturally spawn unfortunately you can only get mobs on you island through eggs or a spawner unfortunately