Wait, mechanoids can drop through overhead mountains?

[code99xx]

Title.

Can they do that?

[Limdood]

Not as far as I know. 

Did you maybe have a section of the map that was an "area revealed" that you later roofed over as part of your base?  It would have had no roof or thin roof, and thus drop pods COULD land there, even though the entire surrounding area is overhead mountain.

[B@R5uk]

code99xx, there is this button with home icon in the right bottom corner called "Toggle visibility of the roofs." (Actually there is two "home" buttons; you need the rightmost one, without door and windows) Check it. Every cell with roof will turn light green and mountain cells will have dark green colour (that which aren't hidden in the fog of war ignorance). Through every light green roof transport pod can land without problems even if it's just one cell in the middle of your mountain base. So if you wand to prevent landing through such sell you should build any wall in it.

Also, when drop pods land in the immediate vicinity of mountain cells they will be collapsed and ruin everything in such cells. So plan your base wisely. I personally use dev mod tools to disable fog of ignorance.

[Kirby23590]

Yes... Also Raiders do that as well...

It can be very annoying if they break into your mountain and that's where your entire stockpile is...

There are some mods that completely remove that kind of raid dropping in the center of your base. But there are other ways to counter that, some players have been putting turrets in side their base or building killboxes inside their base.

[code99xx]

Right, so I guess there were some spots where it wasnt overhead mountains. I'll have a look at that (didnt think this was possible).

Thanks!

[TheMeInTeam]

Yeah you can have areas that just count as normal thin roof.  This is almost always the case just as you begin tunneling into a rock structure, but the layout of the mountain itself can have thin rock too.