If you could look at all of the quests/missions in a game and the connections between them, most games would form a linear line. That's actually kind of sad. RPGs tend to do a little better and many times will form a tree. In Din's Curse (and also Depths of Peril to some extent) they form a web. A very dense web at that.
I have added a good example of how this works lately to the game: the darkness machine. This is a machine that once built causes the entire area to get much darker than usual. This doesn't sound too bad except it screws with the local crops so food prices go up. Monsters tend to be much more aggressive when it is dark so the town you are trying to save is much more likely to be attacked. Also now that one machine is up and functioning it encourages other monsters to build other machines to wreck havoc on the town (like earthquake or weather machines).
So there are lots of strands that leave the darkness machine quest, but what leads to it? Well a lot of things frankly. Most unique monsters, bosses, and unique monster groups have a chance to secretly build them. Just because you know about a monster already doesn't always means you know what they are up to. Hurry up and kill them already! You might discover that someone is building a darkness machine in the dungeon and have a chance to disrupt the plans. If you fail, you will have the darkness machine to deal with and whoever built it. Sometimes you only get partial information and find out that someone is building "something" in the dungeon. This could be a darkness machine or it could be something entirely different (although whatever it happens to be is probably dangerous for you). Sometimes your information is really bad and you just find out someone is planning something. This could be anything from a town raid to yep, you guessed it- building a darkness machine. As I implied before, if someone has already built an earthquake or weather machine this might also lead to someone building a darkness machine.
Like I said, the quests are very web like. There are many different things that lead to each quest and many possible other quests it can start.
It will be interesting when people get into the situation where they have darkness, weather, and earthquake machines all needing to be destroyed.
