I think it was Zak that made an offhanded comment about it being impossible to make a random chart to generate tricks, which I took as a challenge. I haven't succeeded, but I haven't given up yet.
My idea was to create a roll-all-the-dice spur, which would be fairly abstract and let you, as DM, figure out exactly what it meant in detail. One column would be "origin"-- where did this thing come from--because that really informs tricks and puzzles. I did some thinking on origins and thought I'd share.
First a bit about nomenclature. "Traps" are easy, they are set intentionally and are meant to capture or kill you. I don't really like the word "trick" because it seems to focus too much on the aspect of these things as intellectual obstacles that the DM places in front of players. Delta has explored the preponderance of these things in the early game charts and texts. But features of the dungeon can be more than chutes, slides, and elevators. Another term often used is "puzzle" and while it seems more appropriate in that all these features are puzzling, it has the connotation, for me at least, of something that must be solved for the adventure to continue. Maybe not necessarily, but these things take mental effort on the DM's part and I think that means they are often central to exploring parts of a dungeon or retrieving a treasure.
I don't have a better term to offer, so I guess I'll call these tricks. Whatever we call them, they seem really important in that these are the spots where the Mystical Underworld gets right up in the faces of the players and makes them deal with the fact that things are not normal. And knowing that as DM can be enough to design them-- think of interesting weird ways to make players interact with the dungeon environment. But I think if there isn't too much of a price to pay, including verisimilitude is always a plus. In other words, interesting features first, but if we can answer "Why is it here?" it would be a bonus. Hmm, maybe I'm contradicting myself here; the Mystic Underworld doesn't need reasons. Well, if nothing else, thinking about the "why" can help us generate. So, what are the types of tricks?
I. Arcane Test
These are checking to see if you know what the maker thinks you should know. All the tricks in my Alabaster Tower would fall under this category. Getting through the tower is supposed to mean you have passed an initiation, and each trick tests particular tenets the wizards thought initiates should know. But more than that, it is testing a mindset, "Are you the type of person who studies the world, examines things thoughtfully? Or, will you start hacking at stuff and get yourself stung to death?"
Cults, secret societies, and lost tribes seem likely makers of this type of trick. They should be based on some kind of principles, philosophy, or shared knowledge that the group would be expected to know. They might not necessarily be deadly if someone interacts with them incorrectly, but there should be enough of a disincentive to not allow someone to experiment and discover how to pass the test through trial and error.
And because these will often be about preventing access to the hallowed chambers of the makers, these types really blend into the next type:
II. Fantastic Lock
I see these more as a combination lock to allow only certain people through. But while they may use the trappings of philosophy or historical knowledge, the only test the user is expected to pass is: "Do you know the combo?"
I think these would be more likely to be used by individuals-- powerful mages, or chieftains-- and if by groups, most likely secular organizations. I think they are more likely to have dire circumstances if you get the combination wrong. And these, because they serve the practical task of opening a door (however convoluted each implementation), they blend into the next category:
III. Alien Machine
If you strip our knowledge and context about things everything becomes weird. Imagine someone from 1300 trying to figure out a microwave. Domestic appliances, tools, apparati manufactured by ancient elves, or aliens, or shoggoths seem equally ripe for puzzling magical weirdness. A chest that dehydrates anything put in it, a cabinet that gilds objects placed in it, or even weirder things.
These would more likely be found in the remnants of long dead civilizations. They seem least deadly of all tricks, and potentially useful to the crafty party that figures them out.
This category would also contain things that are not actual machines, but had a purpose at one time, or are the evidence of past intelligence even if they have no particular function. I'm thinking of B1's pools now. The next category might be similar in that it is perfectly logical, and only odd because we lack the context:
IV. Environmental Oddity
The difference is that these are not manufactured they are geological, biological, or maybe meteorological effects. I think some of my creature features could fit here. Geysers, musical algae, whatever.
V. Whimsical Obstacle
This is the classic Zagyg is just screwin' with ya. Sure the fountain of gender exchange may be an alien machine long abandoned by the shoggoths, but it's more likely some insane mage or trickster god is having a laugh at you.
These could be completely random, both in their location and their effects: anywhere from certain death to butterfly swarms.
Can you think of other categories than these five?
One difficulty for players having to make decisions is how do you tell a type III from a type V, which might drastically affect your longevity. I'm thinking a DM would need to be careful about what decision signposts they give players.