Randomisation in games

Randomisation can cast a huge influence on gameplay, atmosphere and even how players connect with each other. I want to write about it to understand it better and explore how I can use it in my own projects.

What is randomisation?

For the purpose of this post it’s any part of the game that changes based on random numbers to mix up how a game is played each time, or some procedural generation of parts of a game.

The more a game changes between sessions the more replay value it has, but I’m fascinated by this subject and I think there’s a lot more to randomisation than that.

It can be part of the atmosphere and narrative

One of my favourite games, This War of Mine, has a ton of randomisation. It’s a survival simulation based on civilians living through a war, scavenging and tacking difficult choices and potential threats from NPC soldiers and other scavengers. This randomisation contributes massively to the atmosphere and realism of the game. It’s a game about responding to events, not controlling them, so an unpredictable world makes sense. The length of the war can be randomised, and so are the starting home base locations, loot drops, the visitors, the people who may join the group, and world events. All of this creates a far more engaging and realistic world.

Another game I’ve enjoyed playing many times is Stellaris – a 4x grand strategy game set in space, where players colonise worlds and create empires. The universes are created procedurally, and that’s important to me as a player because it means each playthrough I’m discovering that universe for the first time. It adds a sense of freshness, exploration and realism. I’m always wondering what’s in the next solar system and motivated to keep exploring to find resources.

It encourages players to connect and value their experiences more

When players are having unique experiences they want to talk about it. I see this a lot on forums for The Sims. People share stories of events in their games and pictures.

Another shareable experience is map seeds. Players spend a lot of time on forums posting and trying out map seeds for Farthest Frontier, a detailed town builder. And I can see why they’re so engaged with this, because Farthest Frontier has one of the best procedural map generators I’ve seen. It turns out so many beautiful maps that feel so different in atmosphere, and play hugely differently because of their varied terrain and strategic resources.

Whatever happens in a game, if it’s interesting and unique, players will value it more and want to talk about it.

Bringing the game world to life

Whatever version you’re playing, The Sims is a game filled with random events, so many that they combine to create endlessly new situations. From the weather to who arrives at a lot, phone calls, how sims respond to each other’s actions, getting sick, alien abduction, winning the lottery, power cuts. There’s even a volcano that sometimes erupts in The Sims 4. A game world with this much stuff going on feels real and engaging and it has huge replayability.

Interestingly, despite so many events being generated by the game at any moment, it’s actually a game where players create the story. It sounds paradoxical, but the game world is everything for creating an immersive, living world and yet knowing there’s no deliberate pattern here gives the players freedom.

The Sims also has randomised NPCs who have their physical attributes and clothing randomised. This too makes the world dynamic and different for each player.

Replayability

A major benefit of randomising elements of a game is keeping it engaging each time it’s played.

Phantom doctrine – a turn based espionage game – switches around loot drops and objectives while reusing maps. It’s simple but very effective at keeping players engaged because they have to change up their strategies and how they approach the tasks. The guards also follow somewhat random patterns, although I can tell there’s some coding to keep them in general locations – unless and alarm is raised.

A game which has even more random guard behaviour is The Marvellous Miss Take – a high speed stealth game where you rob art galleries – and this makes for different gameplay each time despite the maps being unchanging. The game has a lot of strategies to keep the game replayable and fun however, and I want to write more about them soon.

Random vs fixed?

I’ve been saying loads of good things about randomisation in games, but there’s also times it doesn’t make sense. Fully controlling the game world to create the exact player experience intended can allow for detailed environments and storytelling. Less replayable, but the most impactful playthrough, and that too has a great deal of value.

Many games I enjoy rely on bit of both. Some features exactly defined, but also some quantity of random.

Invisible Inc. is an interesting example of semi-random map generation in a genre that doesn’t usually do any kind of random map generation. It’s a turn based spy/infiltration game where you direct characters to various objectives in a limited time. The maps are generated from predefined rooms that are combined in random ways.

Conclusion

Randomness can make games more engaging, build atmosphere and realism, and even encourage players to connect and share experiences outside of the game, but the randomised influence still needs to be bound within logical constraints. Some parameters need to be determined and set so that map seeds never make a two tile island surrounded by water, or for enemy NPCs to become wildly over powered.

Figuring out what to randomise and the best parameters in my future projects is going to be interesting.