Is there a flag we can implement to make them not targeted by animals, or patrol helis? (if equipped with a t3 kit helis constantly head straight for them and shoot nonstop - invul flag set but it just keeps attacking forever)

you runing any heli mods?

No just regular default heli

I have a few NPCs gathered at a custom outpost type monument in the map and the heli just comes straight for them and attacks the building until its gone despite my zone flags

I also get this about 16 times an hour

Failed to call hook 'OnEntityTakeDamage' on plugin 'HumanNPC v0.5.4' (InvalidCastException: Specified cast is not valid.)
  at Oxide.Plugins.HumanNPC.OnEntityTakeDamage (BaseCombatEntity entity, HitInfo hitinfo) [0x00097] in <7cd79b4b5ebc4b1eb35ab48e7f39905b>:0

  at Oxide.Plugins.HumanNPC.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x00bfe] in <7cd79b4b5ebc4b1eb35ab48e7f39905b>:0

  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <9c80d821d00a44c9a24497c73ad2d20d>:0

  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000de] in <d646191a355d43a6b3ab36b7ee14c740>:0

  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <d646191a355d43a6b3ab36b7ee14c740>:0

Ya not heard of this hapening to anyone else as of yet. Are you using oxide or carbon?

oxide

I keep getting attacked too. I don't have the patrol helicopter plugin.
So I put the NPCs in a zone with no helicopter targets
but now I'm being shot at by the NPCs at the outpost even at the outpost.
What's more, I'm also bothered by the fact that nothing happened for the first few hours, but then I suddenly started getting shot at.

im use oxide too