From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 17 Oct 2018 19:17:27 -0400
Subject: [PATCH] MC-50319: Check other worlds for shooter of projectiles

Say a player shoots an arrow through a nether portal, the game
would lose the shooter for determining things such as Player Kills,
because the entity is in another world.

If the projectile fails to find the shooter in the current world, check
other worlds.

diff --git a/src/main/java/net/minecraft/server/IProjectile.java b/src/main/java/net/minecraft/server/IProjectile.java
index ea5f5845a8d202e62da3ae1bfb1e4dbd7f5e185e..ef7e036943bfbd869bd5d71bcb2ecc6c35c18294 100644
--- a/src/main/java/net/minecraft/server/IProjectile.java
+++ b/src/main/java/net/minecraft/server/IProjectile.java
@@ -29,7 +29,18 @@ public abstract class IProjectile extends Entity {
 
     @Nullable
     public Entity getShooter() {
-        return this.shooter != null && this.world instanceof WorldServer ? ((WorldServer) this.world).getEntity(this.shooter) : (this.c != 0 ? this.world.getEntity(this.c) : null);
+        // Paper start - MC-50319 - shooter might be in another world (arrows through portals)
+        Entity entity = this.shooter != null && this.world instanceof WorldServer ? ((WorldServer) this.world).getEntity(this.shooter) : (this.c != 0 ? this.world.getEntity(this.c) : null);
+        if (entity == null) {
+            for (WorldServer world : world.getMinecraftServer().getWorlds()) {
+                entity = world.getEntity(this.shooter);
+                if (entity != null) {
+                    break;
+                }
+            }
+        }
+        return entity;
+        // Paper end
     }
 
     @Override