1 and is recorded on the entity, so it survives restarts and unloaded chunks.
Where a level comes from
Scaling by distance
A spawner withworld-scaling: true sets the level from how far out it is instead of a fixed number — the further from world spawn, the higher the level.
config.yml:
Reading a level
In any effect text — messages, titles,setname, command:
Both read
1 for anything that was not spawned with a level.
From code, NMEntitiesAPI.spawners().levelOf(entity) returns the same value — see Spawners in the API section.
