Mystery rooms

[Coppermantis]

So they're found in extremely large buildings, right? The only ones I can think of are the Pyramids and the huge buildings in the Ice Age regions. Are there other valid buildings for this? I'm not finding any large ice age buildings at all (Are they really rare now? I've searched many regions, it might just be bad luck) and the continent I'm trapped in by windstorms has no deserts. I'd like to be able to do one of the mysteries but alas I'm not sure what's a valid target to look for.

[Wanderer]

Ruins in abandoned towns have them too.

Simple rule of thumb: If it can have a maze room, it's got a chance at a mystery room, as far as I've seen.

[Toll]

I think it was said the three towers in the lava regions can have them too.

[Coppermantis]

Thanks, I'll go search lava regions and towns then.

What color are the rooms on the dungeon map?

[kuliksco]

Thanks, I'll go search lava regions and towns then.

What color are the rooms on the dungeon map?

as far as i can tell they were the same color as the secret missions.

[Calli]

Thanks, I'll go search lava regions and towns then.

What color are the rooms on the dungeon map?

as far as i can tell they were the same color as the secret missions.

Yup - that slightly more intense yellow-brown that tells you it's not a stash room.  If you hover your cursor over the room in the dungeon it'll tell you if it's a rescue, secret mission, or mystery room.