Well yeah so I tried this:

@SubscribeEvent
public void eventHandleri(RenderGameOverlayEvent event)
{ 
	if(event.type != ElementType.ALL)
	{
		if(event.type != ElementType.BOSSHEALTH)
		{
			if(event.type == ElementType.CROSSHAIRS)
			{
				event.setCanceled(true);
			}	
		}
	}
}

 

and I get this:

 

Am I doing it wrong, or is this a bug? I am using forge 10.13.3.1358.

Well, the first 2 if-statements are useless with the third one, so you can get rid of the first 2 if-statements. But that shouldn't affect the boss health bar...

I just added stuff to make sure, but it never helped.

Great, that works. Thank you!