@mobsRadius - NMEntities Docs

Targets every living non-player entity within N blocks of the mob. Like @entitiesRadius, but players are excluded.

- damage{amount=6} @mobsRadius[8]

When to use it

Use it when players must stay safe from the effect: a boss that buffs its minions, clears out vanilla mobs around it, or converts nearby creatures.

toast_commander:
  model: toast
  base: zombie
  display: "&6Toast Commander"
  effects:
  - run rally #onHurt @self
  rally:
  - particlering{particle=happy_villager;radius=10;points=40} @self
  - heal{amount=6}                     @mobsRadius[10]
  - potion{type=speed;duration=10s;level=1} @mobsRadius[10]

When the commander gets hit, every mob around it heals and speeds up. The players attacking it get nothing.

Details

“Mobs” here means any living entity that isn’t a player. Animals count too, so a rally like the one above also buffs nearby cows. Keep that in mind for effects near farms.
The mob itself is not part of its own radius targets. To include itself in a buff, add a second line with @self.

For the full targeter list, see What are Targeters.

@entitiesRadius @world

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