How do you turn hostile mobs against each other? [duplicate]

Question

I have been thinking of how to make a "mob war" map using the theory that owned projectiles can turn mobs against each other, along with shulkers being able to act as defense turrets for those on the same team. I have tried the {ownerName} tag on projectiles to turn non-shulker hostiles against each other, but to no avail. They appear to have no effect. Is this feature manipulable without plugins? If so, how?

Answer 1

You can turn a hostile or neutral (eg. not passive) mob against another by hitting it with a projectile that is "owned" by another mob:

1. Summon the mob that you want to get angry. This mob mush have specified a UUID:

   /summon <entityType> X Y Z {UUIDLeast:0L,UUIDMost:0L}
   

   Unfolded:

   /summon                      | summon  
   <entityType>                 | a <entityType> mob (eg. Zombie)
   X Y Z                        | at the coordinates X, Y, Z
   {UUIDLeast:0L,UUIDMost:0L}   | with an entity UUID "0-0-0-0-0"
   

2. Summon the mob you want to attack, and optionally add a custom name:

   /summon <entityType> X Y Z {CustomName:attacker}
   

   Unfolded:

   /summon                      | summon  
   <entityType>                 | a <entityType> mob (eg. Zombie)
   X Y Z                        | at the coordinates X, Y, Z
   {CustomName:attacker}        | named "attacker"
   

3. Get the latter spawned mob anger the first spawned one:

   /execute @e[name=attacker] ~ ~ ~ /summon Snowball ~ ~2.8 ~ {ownerName:"0-0-0-0-0"}
   

   Unfolded:

   /execute                   | for all 
   @e[name=attacker]          | entities named "attacker"   
   ~ ~ ~                      | at their coordinates 
   /summon                    | summon
   Snowball                   | a snowball
   ~ ~3 ~                     | 3 blocks above them  
   {ownerName:"0-0-0-0-0"}    | which is owned by the entity "0-0-0-0-0"
   

Answer 2

You could try this as posted here: How do I turn Passive mobs Hostile?

/summon Zombie ~ ~1 ~ {Passengers:[{id:"VillagerGolem",Silent:1b,Invulnerable:1b,Fuse:32767,ActiveEffects:[{Id:14,Duration:2147483647,ShowParticles:0b}]}]}

It will make a Zombie being controlled by a villager golem. To make it hurt things that it touches do this:

/execute @e[type=VillagerGolem] ~ ~ ~ /effect @e[r=1] minecraft:instant_damage

Full credits to this answer to the person who answered on the linked post.