this.fKnockBack = x.xF;

public boolean hitEntity(ItemStack var1, EntityLiving var2, EntityLiving var3) {
      if(this.fKnockBack != 0.0F) {
         mod_NZSwords.knockBack(var2, var3, this.fKnockBack);
      }

      var1.damageItem(this.intEntityDamage, var3);
      return true;
   }