Controlling Mob Spawning with Ender Inhibitors and Death Mufflers
Ender Inhibitors
Ender Inhibitor Inactive is the unpowered state. Ender Inhibitor Active is the powered state. Place an inhibitor in an area to prevent endermen from teleporting or spawning there. Activate it to turn the effect on.
Use Ender Inhibitor Active around your mob farm to stop endermen from teleporting out of the kill zone. This keeps them in range of your Mob Masher or Iron Spikes.
Death Mufflers
Ender Dragon Death Muffler silences the ender dragon death sound. Wither Boss Death Muffler silences the wither boss death sound. Place the matching muffler near your farm if you are killing those bosses and want to suppress the audio.
Tinted Glass
Tinted Glass blocks light while remaining transparent. Use it to enclose spawn areas so light levels stay low and mobs keep spawning, while you can still see inside.
Dark Oak Stone
Dark Oak Stone is a decorative block you can use to build the farm structure. Combine it with Tinted Glass for a dark enclosure that keeps spawn conditions correct.