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 ...
CherionMC on MSNOpinion

How to Build a Mob Trap in Minecraft

This build creates a mob trap that collects drops automatically using redstone and water flow. It is efficient, compact, and ...
To make a mob farm in Minecraft that automatically spawns and kills enemies, you'll need stone, trapdoors, chests, hoppers, slabs, and water.
Experience points (XP) are essential in Minecraft, and they are a must for enchanting tools, repairing gears, and using an anvil in the game. While mining and defeating mobs provide XP, an XP farm ...