The summon action lets you spawn your own custom mobs (more about how to create custom mobs in the custom mobs section). This example will spawn your custom mob named 'customZombie' near the player the disaster was started on.
# This is placed inside an event just like any other action issummon 1:# * The type is the exact name of your custom mob that you defined in the entities sectiontype:'customZombie'target:'player'# Offset will make the mob spawn 10 block radius from the targetoffset:10# If force is set to true then the mob will spawn in the exact location even if its solid blocks, else if set to false then will find an available ground for it to spawn on the Y level (default: false)force:false# If setTarget is set to true then the mob will spawn targeting the player target immediatelysetTarget:true
Here is another example using a location instead of offset. This will spawn your custom mob 10 blocks away from where the disaster was originally started from:
summon 2:type:'scaryMob'# The 'startPos' target is the location where the disaster was started fromtarget:'startPos'location:x:~10y:~0z:~-10