Recently had a Surtling event then a few game days later a skele event on a dedicated server. We have a huge base so didn't bother with either of them. More than a game week later I was out and about in the meadows at night and there were 5-6 Surtlings and a whole group of skeles wandering around killing piggies.
We have killed through Moder on that server but are moving from Plains through the Mistlands so I guess we could get Mistlands events now on our meadows base???
Moral of the story, clean up after events as meandering around the meadows like a noob with low health is a bad idea at night, much more than in the past.