A Hollow Body - Building Resilient Game Experiences With Tech

[No spoilers here]

Making tech-based real-world games is hard.

There are plenty of people better-placed than me to talk about the story, the emotion, the poetry of Circumstance’s guided audio experience A Hollow Body. I want to discuss the implementation.

Circumstance are professionals, and the team for this project included the legendary Duncan Speakerman. So it was oddly reassuring to see that they’d obviously had to work hard on the tech. Noticing details like a reminder to turn on aeroplane mode, a warning to avoid the screen lock, and double confirmation on the “yes, we’re ready” screen are a nice validation that, yes, here be gremlins.

We’re about a minute into the experience when my headphones start beeping. Low battery. My heart sinks. There’s no recovering from this. It’s a 45-minute walk, and if I’m forced to restart the app, I can’t get back to this point. There’s no way to resync, and I won’t even be able to call my friend to recall her and explain what’s going on: her phone’s in aeroplane mode, too.

Now, this is my own stupid fault. Using bluetooth headphones, not hardwired ones, is an extra point of failure that I should have avoided. But, as a rule, players will have broken equipment. Players will show up with smashed screens, flat batteries, weird roaming SIM cards, obscure Android knockoffs with subtly broken browsers. It has to just work, anyway.

In Citydash we mitigated this by using SMS messaging – a technology from 1985! Even in 2014, we ran SMS alongside a modern web-based experience as a backup. It’s only now, in 2015, that we’ve moved away from it. The game is designed to cope with equipment failures: while everyone can interact with the system (at once!), teams of four remain survivable even with only one working phone. The game logic assumes that players will miss messages sometimes, and can recover from a phone reboot or temporary connection loss. And we have the ‘meltdown sheets’, a set of paperwork that we’ve never yet used but can hand out in the case of total technical failure.

Building technology based games requires this level of deep, deep cynicism. A Hollow Body does, in fact, have a recovery mechanism – at the end of each of the three acts, you can pause and resync. But I don’t know that yet.

My headphones continue to beep at intervals over the next five minutes, then fail completely. The audio continues from the phone’s speaker (hooray!), but I can’t turn the screen off without stopping it (grr), so my ear pressed against the screen triggers the settings menu and pauses the app anyway (argh). I fix it, but I’m five seconds behind, now, with no way to skip forwards and get back in sync. It’s distracting, but not game-breaking.

In any case, maintaining sync is much, much harder than it looks. An early Fire Hazard game called Suspected used a custom mp3 track per player – 120 in all – to weave a complex dance along London’s South Bank. The start signal was the chiming of Big Ben, which I’d hoped would minimise the “smear” of start times we’d otherwise see. But, as we found out afterwards, over 60 minutes people get out of sync anyway. Some people had their devices fail and had to guess at where they were up to. Some got calls. Some – and I should have seen this coming – would pause the track to “pause the game”, or replay misheard sections.

In Act 2, we hit another snag. The instructions tell us to follow the road around to the right, but we can’t – the entire road is walled off by construction. We make eye contact and re-route with hand gestures, but the narrative carries on, expecting us to be somewhere we’re not, and we’re getting more and more lost as it walks away from us. As before, we have no controls to rescue the situation – we can’t pause it, can’t even flip over to Google Maps to locate our next reachable destination without doing unknown-but-probably-bad things to the game state.

So we start running, my heavy pack thumping against my back, both of us alert and scanning every direction for details that will let us pick up the thread, swapping nods and hand signals. And suddenly, the experience is not a gentle, dreamy walk through a narrative landscape, it’s a challenge – we’ve got to move, to hunt down an invisible ghost describing its surroundings as it walks away. It’s on!

And that’s another rule. Players will play your game the way they want to, and they will have fun whether you like it or not. I’ve seen someone in a very early Undercover test find their assigned mission impossible (or uninteresting) and go ‘rogue agent’. I’ve even had Citydash players construct an elaborate fake kidnapping of a guard to extort extra points. If players want a game about filmmaking and you’ve got a game about running.. they’re still going to make films.

By the third act we have all our gear working and are into the swing of things, perfectly synced and clear of unexpected construction, and there’s one moment each where the synchronisation really pays off, producing something magical and memorable. And that’s almost another rule of game design: Players will take half an hour to get their shit together. Handhold them for that bit, and if you’re going to do anything really cool, don’t do it at the start. A more recent Undercover playtest had a learning curve like a garden fence – not high, but completely vertical – and boy did we hear about it in the feedback sheets. I’d have liked to see A Hollow Body start with a short chapter and end with a long one, rather than the other way around – although perhaps there’s an aesthetic reason why it needs to be the way it is.

The tech bites me one last time. It’s no spoiler to say that the experience ends suddenly. But at no point does it say “the end” – and when I glanced at the screen for confirmation, I saw a “low battery” warning that could also conceivably have been responsible for the sudden end of the audio track.

I’m sure Circumstance’s scriptwriter would be baffled by my confusion – the ending does makes perfect narrative sense – but I’ve found that players will be uncertain about things that seem obvious. I have actually had a team show up to a playtest, not notice the obvious-to-me-the-designer “Ops” tab on the game app, and spend an entire hour trying to play the game without seeing anything but the basic briefing. If it’s important, then ten-foot-high letters of fire are probably just about clear enough.

It’s a testament to the solid design of A Hollow Body that it’s able to recover from player-induced problems like these. But quite apart from engaging with the story and being moved by the soundtrack, I also found it very reassuring that, when I’m designing games and wrestling with tech problems, I’m not the only one.


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