EntityJoinWorldEvent is fired when an Entity joins the world. If this event is canceled, the Entity is not added to the world.

You will need to cast the event in the function header as this class:
crafttweaker.event.EntityJoinWorldEvent
You can, of course, also import the class before and use that name then.

EntityJoinWorld Event implements the following interfaces and are able to call all of their methods/getters/setters as well:

• IEntityEvent
• IEventCancelable

The following information can be retrieved/set during the event:

ZenGetter	ZenSetter	Type
ZenGetter world	ZenSetter ​	Type IWorld

The following information can be retrieved/set during the event:

ZenGetter	ZenSetter	Type
ZenGetter entityLivingBase	ZenSetter ​	Type IEntityLivingBase
ZenGetter canceled	ZenSetter canceled	Type bool

ZenMethods

• event.cancel(); Method, returns void (nothing). Can cancel the event and stop something from happening