Originally posted by Cadillac:

I've been playing for several days now. killed two bosses but still no raid events appear, only some isolated monsters but no raid event.

any ideas?

According to what people have discovered is you need to be in render range of a workbench which is part of 3 or 4 structures. When the hidden timer goes to trigger it will start. If you're out in the woods hunting, mining, etc it won't trigger. I went weeks without an invasion. Then I build a workbench, some simple walls and a chest to dump all my ore halfway to my base. Minutes later a wolf army attacked.