I call onDeath method, and the game is crashed.

The game is crashed in LivingEntity.dropLoot method.

protected void dropLoot(DamageSource damageSourceIn, boolean p_213354_2_) {
      ResourceLocation resourcelocation = this.getLootTableResourceLocation();
      LootTable loottable = this.world.getServer().getLootTableManager().getLootTableFromLocation(resourcelocation);
      LootContext.Builder lootcontext$builder = this.getLootContextBuilder(p_213354_2_, damageSourceIn);
      loottable.generate(lootcontext$builder.build(LootParameterSets.ENTITY), this::entityDropItem);
   }

getServer method always returns null.

@Nullable
   public MinecraftServer getServer() {
      return null;
   }

This causes NullPointerException.

Edited January 27, 20205 yr by kyazuki

Show your code.

Can I check Client or Server Thread by isRemote()?

@SubscribeEvent
  public static void killPlayer(TickEvent.PlayerTickEvent event) {
    if (event.player.world.isRemote()) {
      if (/* check player */) {
        event.player.onDeath(DamageSource.OUT_OF_WORLD);
      }
    }
  }

I assume that I must call onDeath in Server Thread...

Thanks!!