Not Peaceful Detector

A device which uses a modified zombie spawner to detect whether players in range are on peaceful or not.

If they aren't in peaceful mode it will emit a redstone signal. You can invert the outputs (put a redstone torch in front of the repeaters) so that it will emit a redstone signal when they ARE in peaceful mode. In the download it's designed so that the signal can be drawn from any point around the device, but you could isolate the outputs (remove the redstone around the sides) so that you can have 4 separate outputs which will turn on and off randomly.

It is faster, more reliable and less CPU intensive thereby producing less lag than other similar devices. This is because when a player in range is not on peaceful it will spawn 5 zombies simultaneously 8-16 ticks after the player comes within range. Normally it would spawn 1 zombie at random intervals up to 120 ticks after the player comes into range.

You can choose any detection range for the spawner from 4 (which is the block next to the device) to 16 (normal detection range) and I've added 32, 64 and 128 blocks detection range for long-range purposes.

I originally designed it for use in my adventure map "Nether Collapse" to only open a door when the player has turned peaceful mode off, but I thought others might find it useful so what better place to put it than PM.