You can set spawn-mobs: to off in server.properties. Wait. Are mobs even implemented in PocketMine yet?
Why squids Don't explain if it's too complicated for a 12 year old who just started learning PHP OOP.
@shoghicp randomly decided to implement them while he was the lead developer. No one really knows why https://github.com/PocketMine/PocketMine-MP/commit/69f841a00ca3f97b8aaf92312f3f98361b786500 https://github.com/PocketMine/Pocke...69a34f7#diff-59686adaecba09f8191fa3c506d6e9df https://github.com/PocketMine/Pocke...0b1e376#diff-16fc0cdae9a99b9af4a2c26284bbeb15 That took some serious digging to find those!