For mobs to spawn very efficiently you want to be 128 blocks away from any other potential spawning points for them (blocks with block light lower than 8), so you should be 128 blocks above the highest block in an 128 x 128 area around your spawner.
How close do you have to be for mob spawners to work?
In the case of a spawner, players need to be at a distance of at least 16 blocks distance from the spawner to activate it. When AFK-ing at a spawner-based farm, players should be at a distance of less than 16 blocks from the spawner.
What does the 24 block rule mean in Minecraft?
As pointed by MrLemon in the comments the 24 block rule may refer to this as quoted from minecraft wiki This means that you should stand 24 blocks away from any thing that the mob can spawn at. Simplest way to do this is to Build it about 30 blocks above you, have the mob fall 22/23 blocks as explained below and stand there while afk-ing.
How many blocks does it take to spawn a mob in Minecraft?
The spawner will only spawn mobs if a player is within 16 blocks of it. A common trend among seasoned players is to create mob traps around mob spawners for an easy way to gather that mob’s resources with little or no danger to themselves.
How long does it take for the spawner to spawn in Minecraft?
The [&spawner&] [&spawns&] mobs in a 9×3×9 area (see § Mechanics) around it when the player is within 16 blocks. Suitable spawning locations for the block’s mob type are provided in the area. The [&spawner&] attempts to spawn four mobs around it, then waits from 10 to 39.95 seconds before spawning more.
Where do you spawn in Minecraft if there are no grass blocks?
However, if there are no valid grass blocks within the world spawn area, the player spawns directly at the world spawn point. Upon spawning, the player is placed on the highest block of the X and Z spawn coordinates, even if this would set the player above the maximum build height.
