A key fact about Agatha's Dingbots is that they self-replicate, but don't do so very well. The primary generation, built by Agatha herself, are very high-quality Clanks -- indeed, Dingbot Prime is one of the best. The ones they build aren't as good, though, and they ones they build are starting to break down. Fourth generation Dingbots just don't happen: they are too poorly built to activate.
So the plot is that, just before vanishing and being turned into Maria, Agatha had been playing with a new model of Dingbot the night before. This new Dingbot doesn't really do anything very well, except make more Clanks exactly like itself. But it does that extremely well. As a result, we are faced with a grey goo of Dingbots, constantly building more and more of themselves and getting underfoot.
This isn't an easy plot -- it doesn't have a lot of obvious character-on-character interaction. But it provides an appropriate threat that everyone can agree upon, and a good reason why everyone needs Agatha back, and might give Dingbot Prime a primary plot. So it's worth mulling over ways to make this work in-game, keeping in mind that the Replicator Dingbots really have to just be item cards.
Thought: Perhaps there's something in the castle which prompted some of the Dingbots to turn Replicator - something that changed their programming, so to speak, or gave them an external source of power / oomph / intelligence permitting them to surpass the usual three-generation limit. --Darker Justin: Good idea. It also implies that the Castle holds the solution to the problem, which is good, because I hadn't actually given much thought to the answer here. And it ties things together, which I always like...
If we do wind up with a lot of Dingbots, we should probably represent them with props. Each Dingbot could be a common household thing -- anything from a funnel to a cup -- with a single googly eye pasted on. See (v5, p34) for a look a nice little lineup of modern Dingbots.
Justin 12/20: A rather different view on the idea, to consider. The problem with Replicator plots is that they are dangerous. They're not easy to stop, and the naive implementation of the plot is pretty apocalyptic. So we might have to swing in and "save the game" if they players don't stop it, which I despise doing.
That said, we haven't yet discussed the possibility of the Replicators having motive. That is, maybe they aren't just gray goo -- following Darker's idea above, maybe there is a reason they were brought into being. That motive might not be as horrible as it seems; it might even prove to be benign, once everyone understands that the "threat" isn't what it appears.
Which leads me to the insane thought: y'know, I really want to bring Winslow into this game somehow. And I find myself with this loony image of this thing that appears to be a stuffed puppet sitting in the Castle, which is actually a godlike interdimensional being trying to get home again, but who needs all those little clanks working together in order to do so. It's so consistent with the way Winslow tends to appear in Foglio stories (where it always straddles the line between goofy and omnipotent), and adds a whole new strand that can tie neatly into the uberplot...
Justin 12/30: Okay, putting together the tweaked plot. The night before game time, it was Dingbot Prime, not Agatha, who was compelled to build a new kind of Dingbot. It built it and watched it go off on its way, and didn't think too much more of it. But today, it is observing more and more identical little Dingbots popping up, and they aren't following its lead. Instead, they just keep building more of themselves.
This plot wants to evolve as the game progresses. The first hints should be visible in the background material, and further hints should be dropped around hours 1 and 2. By halfway through the game, Dingbot Prime should be seriously worried, and tring to figure out how to express the problem. Around hour 3 (if the players haven't somehow stopped them), the Sorcerer's Apprentice music should start up (on the boombox that represents the Silverodeon), and the Replicators should all start marching towards the Hidden Castle. There, they try to take control of the Mirror of Amagog. And if they aren't stopped from that, they dial it to the strange world that Winslow comes from, which causes him to come to life, and maybe to grant one wish to the one who gave him back his life: Dingbot Prime.
This plot needs some work. The broad strokes are okay, but needs players to have a more active role in steering it, so they get more out of the resolution. Maybe it needs something from Dingbot Prime to come out well? Possibly the reprogramming of the Silverodeon is a crucial part of the process -- music is so central to this world, it's entirely reasonable to think that the "music of the spheres" is required to focus and control the Mirror of Amagog, and that specific melodies tune it to specific places. That works nicely, and means that musical skill suddenly becomes one of the more important talents in the game.
Note that this plot inevitably overlaps with Dingbot Studies. Think about how they cross over. At the least, Silas and Beetle have been observing Dingbot Prime specifically to see how it constructs other dingbots. They shouldn't realize upfront that the replicants are all identical, but the GMs should twig them to it at some point. Possibly each dingbot has a fine-grained description, so it's possible to notice that those of the replicants are all identical.
Characters In Game: Agatha Beetle Dingbot Prime Silas
All Characters: Agatha Beetle Dingbot Prime Silas
This plot has one really serious problem: it is really in no way player-driven. Indeed, the way it came out, it is entirely mechanical. That must change next time. We should probably make this plot much more actively driven by Dingbot Prime, and be more prepared for it to simply go in unpredictable directions. That will take more and better writing, but it ought to be manageable.