The ExplosionStart Event is fired shortly before an explosion starts. If canceled, the explosion will not happen.

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

ExplosionStart Events implement the following interfaces and are able to call all of their methods/getters/setters as well:

• IExplosionEvent
• IEventCancelable

The following information can be retrieved from the event:

ZenGetter	ZenSetter	Type
ZenGetter world	ZenSetter ​	Type IWorld
ZenGetter explosion	ZenSetter ​	Type IExplosion
ZenGetter position	ZenSetter ​	Type IBlockPos
ZenGetter x	ZenSetter ​	Type double
ZenGetter y	ZenSetter ​	Type double
ZenGetter z	ZenSetter ​	Type double
ZenGetter canceled	ZenSetter canceled	Type bool

ZenMethods

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