You can now spawn a prefab in places where a specific ore deposit touches the surface.
See, there are the features on the first page that entice most players, and then there's stuff like this that make the modders salivate.

ray:
My test zombies kept going for the trader in my test levels if I kited them too close.
I hope it was Trader Rekt, for, um... science reasons. :spy:
On Z's climbing ladders with broken 1st rung-gate, I think we need some "safe" way into our bases. Otherwise we have to jump gaps or some other thing. In other words, I'm not sure "fixing" this problem would be a good thing, IMveryHO. #Fataalismakingzombiestoosmart
What makes the game interesting to me are methods that improve safety, without offering
total safety.
There's a scene in The Walking Dead where Rick & company dash up a ladder with an urban horde of zombies hot on their tail. The zombies cluster around the base of the ladder, with a few reaching towards the first rung experimentally. One gets the sense that given enough time, some zombies would 'figure it out' and ascend the ladder, but after a momentary delay the heroes pull it up so the zombies can't even try.
That was perfect for me. Had Rick stood smugly and securely at the top of the extended ladder, not bothering to pull it up, it would've ruined the sense of danger. Had the zombies effortlessly scrabbled up the ladder or the walls, it would throw in to question why the heroes aimed for higher ground in the first place. What was best for dramatic purposes, and what I believe would be best for gameplay purposes, is for ladders (and all other tactics) to
help against zombies without nullifying the threat. The consequence would be yes, players use them, but in concert with other techniques.
Similarly, zombies should be able to jump or otherwise cross a gap. But it should slow them down, or only a subset of zombies should be able to cross, so that a jumped gap type entrance like you mention isn't useless, nor is it foolproof.