Minion spawn points?

[Merudo]

I don't understand where the minions spawns (especially in the outdoor area).

For example I closed the door to the first town but somehow minions make their way there.

Also, did anyone try putting a brassier on where guard minions spawn? Does it stop them from showing up?

[terkio]

The creature spawners are invisisible and can be at any place. One rarely see this happening, the creature just materializes from thin air at a specific place.