How would i make Infested Attack Waves just like in WOL

So yuno how in that one mission in WOL where you have to destroy the infested buidlings? was curious how to make a infested attack waves for some reason. but I just wanted to do that sense I wanted to make a infestation based map. Thanks!

There are lots of ways to do this, but I’ll say the two simple ones:

From data:
create a Spawn behavior and put it on the infested building, make it spawn “x” amount of units (infested) per “x” amount of seconds. Then just make a trigger that sends these units with the Issue Order action and use type “Target Point” to designate an attack point (center of your base for example).

From Triggers:
Set up a trigger with parameters:
Event: Periodic Event (makes it happen every “x” seconds")
Action: Get the “Pick Each Unit” one, put in your infested building for it then in that parameter below in that “Pick Each Unit” action, put a “Create Units” action, then select “Picked Unit” as the coordinates to spawn it on the infested building.

How would I make a spawn behavior exactly? sorry, just a beginner.