This plugin attempts to help players create reliable and efficient mob switches.

What is a mob switch?

Mob switches are a construct that allows players to conditionally limit the natural spawning of new types of mobs in the world. When activated, the mob switch prevents new mobs from spawning. When deactivated, normal mob spawning occurs. The mechanisms are well documented in the community, but the basic mechanics are to create a large number of mobs of the needed type in a single chunk, manipulate them so that they will not despawn, and then to force that chunk to stay loaded while you wish mob spawning disabled. LogicalGeekBoy has an excellent video on creating a mob switch to disable monster spawning in the overworld.

How does this plugin help with mob switches?

This plugin does not solve the problem of creating a large number of mobs or how to keep them from despawning (again, LogicalGeekBoy's video is helpful here). However, it does improve the reliability of mob switches by keeping the chunk loaded without the need to create a separate chunk loader. It also reduces the server load introduced by mob switches in two ways. First, it eliminates the need for a portal-based chunk loader. Second, when activated, the mob switch deactivates the AI and awareness of the monsters in the chunk. This substantially reduces the server load. Indeed, having a mob switch activated can now be a net-improvement in server performance.

How do I create the mob switch?

Assuming that you have already generated the monsters you will need and gathered them into a single chunk, place a redstone lamp in that chunk. Place an item frame on the redstone lamp. Finally, place a respawn anchor in the item frame. If done correctly, the item frame should disappear so that it will appear that the respawn anchor is attached directly to the lamp. You have now constructed the mob switch. To activate the switch, apply redstone power to it. The simplest way is to place a lever directly on the switch. When powered, the plugin will disable the monsters and keep the chunk loaded. This should be immediately noticeable in that the monsters in the chunk stop moving and making sounds. If you have sufficient monsters in the chunk, natural monster spawning should stop in the rest of the world.