Once you've made a map in "Minecraft," you can craft banners to mark off special points in the world.

To make a mob farm in Minecraft that automatically spawns and kills enemies, you'll need stone, trapdoors, chests, hoppers, ...

You are going to need a lot of blocks for this build so you should better get to farming. As for the blocks themselves, you can pretty much use anything. Cobblestone and Wood are the most common ...