This article was originally published on the Black Armada Patreon – please help us create more great games and gaming content by becoming a patron!

Whenever I GM a mystery game, I aim to create a sense of something that is still happening. Just wandering around collecting clues to solve a puzzle is fun, but I find that it adds a real sense of verisimilitude, but also urgency, when the mystery continues to develop after the investigation begins. I do this by creating a list of events that I can drop in as the investigation proceeds. This also has the benefit of giving the players stuff to respond to even if they’re totally failing to make any progress in their investigation.

The point here isn’t to treat it like a linear experience where you have to go through the full list. You could do that, and it might be fun, but it might also end up feeling like the players’ actions didn’t matter – after all, you made them go through the full list of planned events regardless of what they did. (I often think this when I play games like Assassin’s Creed – I love the dramatic stuff that happens but I know that I can do whatever I want and 90% of the time it will play out the same way regardless.)

Instead what I like to do is react to how the players are progressing. I do this in two ways:

• Pay attention to how long they’re taking, and release events in a way that reflects that.
• Pay attention to who they’re annoying, and release events in a way that reflects that.

In this way the mystery is responsive to what the players are doing. It feels like what they do (or don’t do) matters.

When it comes to measuring time, I’m not an absolutist about it. I’m not trying to track everything they do and add it up, Gygax-style. Again, you could do that, but it potentially has some unfortunate consequences, if you thought they’d take a couple of days of game time to solve the mystery, but they went off on a side quest or something and it took wildly longer, so that when they get back you have to roll out your entire events list. Realistic, maybe, but not very satisfying. Instead, I pay attention to, and roughly tot up in my head, things like whether they took a lengthy research action, and whether they spent an hour debating what to do next. Also, whether they fumbled a lot of rolls. Again, this isn’t realistic – an hour of debating is on a totally different scale to a three-day research project. I don’t care about the realism, it’s about feeling like what you do matters.

If they do something that I think would really annoy someone, or draws a lot of attention, that also goes in my mental tally. Again, there’s no real attempt to systematize it.

I then dole out the events with an eye to that mental total I’m keeping. The longer the players take, the more attention they draw, the more events I’m going to hit them with.

And the events are chosen to create a sense that the mystery is not finished yet. If it’s a murder mystery, the events might be more murders. Or, I might have the villains try and interfere with the investigation. The events are always rooted in my theory of the truth behind the mystery, so they’ll always feel like they’re part of it, rather than just random stuff happening.

As mentioned above, aside from making the mystery feel alive and real, this has the added benefit that there’s always more to investigate. If the players just can’t seem to figure out what to do, or they keep messing up their rolls, events give them more stuff to investigate. More opportunities to find clues.

By giving out more opportunities to find clues, you do risk creating a sense of a railroad. You probably don’t want the players to feel like no matter what they do you’re going to make sure they find every clue, even if that means you have to have a giant plot monster come and vomit the clues on their head. So I don’t generally use these events as a way to give out free clues – more like, they’re a fresh opportunity to get their teeth into the mystery.

But also, I make sure the events feel consequential, and ideally that they represent things getting worse. Because that means it feels like it matters. You took too long, and so somebody died. You failed a roll, and so things got worse. Even though these are just NPCs, sometimes ones you literally made up to have an event happen to them, it feels like it matters. Players genuinely feel bad when a made-up NPC dies on their watch! And the contrast this creates with the occasions where they are smart and quick and roll well, makes it feel like their choices (and their luck) are important.

This whole thing gets systematized in Ex Tenebris. Each scenario has a Menace track which the GM can mark. As it fills up, more events happen. If it fills up entirely the villains trigger their endgame with the players running to catch up. The Menace track sits alongside the Clue track, and they’re the same length, so you have a visible measure of how well you’re doing, and how much progress you need to make if you want to “win” the investigation.

With Ex Ten, marking Menace is a Move. So the GM can always do it if the players roll a mishap. They can also do it if they take an action which is time-consuming (like the lengthy research action mentioned above), or one which attracts a lot of attention.

In the current version of the rules (subject to late playtest changes), you can have multiple Menace tracks running at a time. While you only ever actively investigate one mystery, during downtime the GM sprinkles some Menace across these tracks. The players then choose one mystery to investigate. They can choose not to investigate a given mystery, but if they do it for too long, more events will happen, so that when they finally get around to it they’ll already be running to catch up.

You can use Menace – or the more informal version of it described above – with any mystery game. It really adds a lot to the experience.

Let me know what cool events have you sprung on your players to liven up the mystery. And don’t forget to check Ex Tenebris out on Kickstarter – we’re live from 9 September to 9 October.