This event is fired whenever an entity is knocked back. The event is cancelable and doing so will prevent the entity from being knocked back. Alternately, the strength of the knockback in addition to the X and Z ratios can be adjusted.

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

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

• IEventCancelable
• ILivingEvent

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

ZenGetter	ZenSetter	Type
ZenGetter attacker	ZenSetter attacker	Type IEntity
ZenGetter originalAttacker	ZenSetter ​	Type IEntity
ZenGetter strength	ZenSetter strength	Type float
ZenGetter originalStrength	ZenSetter ​	Type float
ZenGetter ratioX	ZenSetter ratioX	Type double
ZenGetter ratioZ	ZenSetter ratioZ	Type double
ZenGetter originalRatioX	ZenSetter ​	Type double
ZenGetter originalRatioZ	ZenSetter ​	Type double

When the event arrives, it's possible that the attacker, strength, or the various ratios have already been modified. You can find these values in the original* variables.