Cobblestone is one of the best materials used to construct platforms and mob spawners in Skyblock considering it's renewable through a cobblestone generator. It has an ID of 4 and is a solid, opaque block.
This block can be used for many things, such as:
- Building platforms
- Building mob spawners
- Get around block
- Hammering into gravel
It's very easy to obtain cobblestone if you have easy access to water and lava. To make a cobblestone generator, you'll need to put flowing water and NOT THE SOURCE BLOCK next to lava flowing into it. This will make cobblestone which you can then mine with a pickaxe. Another way to get cobblestone is using an Igneous Extruder from Thermal Expansion if you have it installed. All you need is a bucket of water and lava and it will generate cobblestone if you select it to generate it. However, if you do not have a bucket of lava lying aroung, dont sweat it. All you need to do is to sieve dirt untill you get four stones. then you can craft them together in a 2 by 2 patteren to get a piece of cobble.