Art is important.  It’s the first thing players will notice about a game – it draws them in, keeps them engaged, and affects how favourably they’ll view the gameplay experience.

I’m not an artist.  For Sub Terra, we borrowed the extensive talents of the wonderful David Franco Campos to provide our environment and character illustrations, and the excellent Zak Eidsvoog to provide the iconography and other graphic design.  I had a picture in my head of how I wanted the visual elements of Sub Terra to look, both functionally and aesthetically.  It was up to me to provide both detailed art direction and feedback so that David and Zak could turn my brainstuff into reality.

Here’s how that went.


Sub Terra takes place deep beneath the surface of the Earth, in a series of unwelcoming, deadly caves.  The players start off trapped at the centre of this cave system, and need to find their way out before their flashlights run out of power and they’re lost in the darkness forever.

The cave is constructed from 50mm tiles in the centre of the play area, and is the dominant visual element of the game.  It’ll be the object that players will look at the most during the game, and the main thing that spectators will see when looking at a session from outside.  The tile art therefore needed to convey this sense of an inhospitable, hostile, alien environment where humans weren’t remotely welcome, and do so in a highly visible way.

Caves are, almost by definition, dark places, which doesn’t mesh so well with “highly visible”.  Most films and documentaries get around this in a realistic way by illuminating the cave through flashlights and lamps carried by the protagonists.  This works well for dynamic media, as the characters can illuminate different parts of the cave as they move and look around, casting long creepy shadows and emphasizing the darkness behind them.  It doesn’t work so well for static media such as board games, however.  Let’s take a look at The Cave:


The Cave is a competitive tile-based cave exploration game.  The players are trying to explore the cave in the best possible way.  While it does have survival elements (caves are always a bit dangerous), the focus is on careful resource management rather than things going wrong and the darkness closing in.  The cave tiles themselves are all illuminated as if lit by flashlights (using a yellow/white/brown palette), regardless of whether a player is nearby or not.  Taken together, the whole cave appears well lit by human light sources, and feels relatively safe.

Sub Terra wanted to do something different.  Ideally, no tile would be illuminated by human light sources, so the players would feel much more isolated and the cave would appear much less safe.  While we could avoid full realism in our lighting, I didn’t want to make the tiles wholly unrealistic as this ran the risk of hurting player immersion.  Thankfully, there are other plausible, semi-realistic ways to light a cave.  Enter the Waitomo Caves, New Zealand:


The Waitomo cave network is best known for its large population of glowworms.  These insects deploy silken nets from the ceilings of these caves and illuminate themselves to attract prey, fooling them into thinking that the cavern roof is the night sky.  They produce a glow in a cold blue or cyan colour, which is eerily dissimilar to the warm yellow tones of most lighting on the surface.

Using this palette for underground environments isn’t new.  Video games often need to take control of environmental lighting to highlight certain areas, paths or objects, or simply to inspire a feeling of awe at a large impressive vista.  Letting the player be the sole source of illumination might be more realistic, but runs counter to these goals.  Here are some examples from Skyrim, Half-Life 2, and Dear Esther:


This felt like the correct approach.  As the Sub Terra cave is viewed from above, the ceiling-based glowworms weren’t quite appropriate, so they were swapped out for floor and wall based bioluminescent fungi using the same palette.



Of course, not all cave tiles do the same thing.  It was important to ensure that the different tile types had their own distinctive look and feel; we could identify tiles using iconography, but things would work much better if the illustration strongly conveyed the hazards as well.  We achieved this through palette and texture variations.  Here are some examples:

  • Gas
    These tiles can exude toxic gas to choke the player.  Given bright green is a familiar fluorescent/bioluminescent colour that’s also associated with poisonous substances, and that ‘gas’ isn’t a particularly visible thing, shifting the palette seemed to be the correct approach here.


  • Water
    These tiles contain a pool of water that can flood, making the tile harder to traverse.  ‘Blue’ is the colour that most strongly suggests ‘water’, but we were already using this for the default cave palette.  We ended up solving this using texture – making the water surface flat and reflective, and surrounding it with a slick, pebbled ‘beach’.


  • Cave-in
    These tiles are unstable and could cave-in at any moment.  The easiest way to suggest this was to place piles of loose boulders and stones on the tile floor, a textural change that hinted at a tunnel close to collapse.


  • Horror
    These tiles are where our shadowy horrors enter the cave and start chasing the players.  The horrors are deliberately mysterious, so we wanted their presence to be implied rather than shown directly.  Our first attempt was just to darken these tiles, but this led to them blending into the rest of the cave rather than standing out.  Instead, deepening the blues and adding bright piles of contrasting white bones fixed this issue.




Players in Sub Terra assume the role of a caver character, each with their own strengths and weaknesses.  It was important that players could comfortably project themselves into these characters to strengthen the bond between player and avatar.

We didn’t need to provide art for these at all – the projection might have been stronger were these left as silhouettes – but it’s often useful to be able to grasp what a character’s purpose is by looking at the art rather than reading the rules.  Character art makes the game look nicer overall, provides player stand-ins for card, rulebook and box illustrations, and establishes a link between the game characters and those in any supplementary media (such as the accompanying graphic novel).

These illustrations needed to match the serious and gritty tone of the game.  While there’s a time and a place for zany comedy (games are meant to be fun, after all), this didn’t feel appropriate here.  I know Dead of Winter’s drunk Santa and lovable stunt puppy are fan favourites, but in my opinion they’re a really jarring contrast to an otherwise dark survival game.


Diversity in games is important for many reasons, but here it had the additional goal of providing characters that a wider swathe of players could identify with.  The gamer population is fairly evenly split between male and female players, and while ethnicity and LGBT data is lacking there’s no reason to believe that any subgroup is more or less likely to be interested in games than another.  We also took care to ensure that the female characters weren’t overly sexualised or drawn for the male gaze – these are supposed to be strong, confident, capable cavers, and any submissive tropes would undermine this sentiment as well as likely causing offense.


During early development, the backstory of the characters and predicament was kept fairly abstract, to allow players space to invent their own.  However, Peter was keen to release a graphic novel alongside the game, which required the characters and their motivations to be fleshed out in considerably more detail.  Before David started on their illustrations, I spent some time giving the team a diverse set of personalities and history.  This turned out to be very helpful when providing art feedback, as we could drop hints into the illustrations through poses, equipment and details, which further distinguished the roles from each other.

I’ll be diving deeper into our character choices in my next post.


Zombies are the most common horror game monster.  They’re individually easy to deal with but terrifying en masse – this allows the players to fight and defeat small groups of zombies, while being careful to not get overwhelmed by a large horde.  This is much more suited to the action horror genre, where combat is a gameplay focus.

In contrast, the Horrors in Sub Terra are each extremely dangerous and very hard to kill.  Combat is not the focus, and indeed isn’t even an option for most characters.  Instead, the main way to deal with the Horrors is to run away, and, if that doesn’t work, attempting to hide.  This is their domain, and they have the upper hand.

But what are they?  Well, we decided not to show you.  It’s accepted wisdom that the monsters in horror movies are scariest before they’re fully revealed.  As soon as you know what something is, you can plan around it, and the threat diminishes.  While something remains unknown, it could be capable of anything, and dealing with it is much harder.  Keeping our Horrors abstract allows the imagination of players to fill in the gaps, and justifies all potential inconsistencies in their rules (e.g. why do they appear only on horror tiles? Why can they easily cross all obstacles?).

A minority of playtesters felt differently about this, so at several points during development I considered making them more concrete (e.g. giant insects, or shadowy troglodytes).  But this was always swiftly followed by a backlash from the majority of testers who preferred them kept in the dark.


Despite David doing such a fantastic job with the illustrations, for the game to function we now had to scribble all over them with icons and text.  The trick, as always, was to do this in as unobtrusive a way as possible.

Zak quickly settled on a “cave scrawl” style for the tile/hazard iconography, and after much discussion we settled on labelling each tile with a small symbol in the corner:


The hazard cards and caver boards are still a work in progress, but we settled on disconcerting slanted elements and distressed icons to try to capture the threat and isolation the characters are enduring:



It’s important to note that the above images aren’t final, but they are what’s made it into the latest set of prototypes.  Over the next month we’ll be testing these extensively and refining everything based on user feedback.  It’s important that the art and design blend seamlessly and intuitively to provide as smooth a play experience as possible, and the only way to check this is by running it past all of you.

In my next post, I’ll be discussing Sub Terra’s diverse cast of characters in detail, and presenting my argument for why varied representation in games matters.  See you then!

Tim Pinder

Tim Pinder

Game Designer, Sub Terra

Indie gamedev robot. All opinions, fatalities and apocalypses are the responsibility of my creators, who should have worked harder on the control problem