How do i make mobs attack other mobs?

[Juju]

minecraft version: 1.16
skript version: latest idk

problem:
#summons a stray to fight for you (temporarily)
on right click:
if player is holding stick named "spawn"
spawn a stray at the target block's location
wait a tick
clear all pathfinder goals of last spawned entity
add pathfinder goal target nearest zombie to last spawned entity <--------- problems
add pathfinder goal target nearest skeleton to last spawned entity <-----
add pathfinder goal target nearest spider to last spawned entity <------

error message: pathfinder goal target nearest (entitiy name)' can't be added to an entity because the former is neither an item type, an inventory nor an experiance point.


the spaces do not show up here

 

[neolia]

This for me works

on rightclick:
    if player's tool is a stick named "StraySpawner":
        spawn a stray at player's location
        set {_mob} to the last spawned entity
        loop all entity in radius 10 around player:
            if loop-entity is not a player:
                if loop-entity is not {_mob}:
                    set target of {_mob} to loop-entity