Super Death Fortress is an iOS artillery shooter which was developed in the first half of 2015 and released in July of that year from Flat Earth Games. The Flat Earth co-founders and brothers Rohan and Leigh Harris share the story.
The game began from a nasty hangover (told by Rohan)
It’s a little strange to do a postmortem on something that’s still ‘alive’. Sure, the game is out and ‘done’, but it’s also a free-to-play game (our first FTP game, in fact) – and we’re still updating, tweaking and making plans for it. But it’s out – the pivotal first few weeks are over and we can begin to look at the game more in the context of what we’ve done rather than what we’ve got left to do.
Super Death Fortress began with a nasty hangover, and a feverish wish that a certain addictive-but-frustrating iOS side-on golf-game (Desert Golfing) would just let me blow the golf balls up – surely that would make even the most irritating of the holes just a little bit more cathartic.
My mind flashed back to the classic Worms and Scorched Earth, and I went from daydreaming about explosions to daydreaming about how I’d make ‘90s-style pixel art explosions… that fully deformed terrain.
Given any modern 3D rendering framework you aren’t usually controlling individual pixels, and this presented me with exactly the kind of challenge I needed to make a three-hour train trip with a hangover slightly more bearable.
Within an hour or two I did indeed have a basic ‘object flings across screen, pixel-dirt blasts apart’ prototype, and I was pretty pleased with this result. I didn’t really know what I was making, but I knew one thing: I found flicking little mortar rounds across my iPhone’s screen and watching dirt explode fun.
Still, blowing up dirt piles wasn’t enough, and I began to remember how much fun it was (twistedly) to see the pixel-art Lemmings blow apart. So I began to draw little soldiers. I spent the next week tinkering on and off with this prototype between work on our current “real” project. By then, I had them sitting there, looking fierce and just waiting for you to blast them into a spray of red gory pixelated mist – and between rounds they’d advance, walking over the increasingly-deformed terrain and preparing to fire pot-shots at the little squat cement fortress I had knocked together.
I was pretty chuffed – the blood sprayed out and ‘painted’ the ground, and little pixelated body parts began to litter the ground. I took my comedy cues from Warner Brothers cartoons – when you blew apart a soldier, he vanished in a spray of mist that obeyed physics, but his helmet? That would sit there just a moment before it settled on the ground.
I wasn’t really sure where I was going with it, but I knew one thing: for some reason, I was enjoying playing this tiny little prototype in my ‘pixel Battlefield’ engine. So I showed it to my brother Leigh – the lead designer for our company.
Battlefields, forts and enemies: rule of threes (told by Leigh)
Rohan and I often discuss prototypes, and have to both agree on one being viable before we decide to work on it in earnest. Super Death Fortress was exactly as Rohan describes – a procedurally generated 2D terrain and a bomb you could fling across the screen – but already it had a fun factor we were used to not seeing until much later on in development (our previous two games being much larger and boasting a multitude of systems).
SDF had passed the test of being something each of us found fun, but it was a mechanic and some feedback – it lacked real structure or sense of progress. This hurdle ended up consuming most of the development time, and was still something which we’re not sure we managed to get right.
The first task was to scope the project, and we conceived it as one having multiple battlefields, multiple forts and multiple enemy types which would unlock in stages. We decided to stick with the rule of threes and give players (at version 1.0) three stages to unlock, each with a distinctive look and landscape. Three forts per stage, each with its own look and special abilities, and three enemy types, each presenting a different threat.
Since we were somewhat happy with the project’s overall playability just a couple of months after conception, we took it to Beer and Pixels, a 100+ strong indie game developer meetup event here in Sydney.
Addictive, then not so addictive – and addictive again (Told by Rohan)
To my relief, the reaction from most people who tried it (an abnormal number of people, actually) was positive. Very positive. We were told it was “addictive”.
Great! But what made it addictive? The fact that it began as a vague idea and not a carefully-designed game made that part a worry. And so we tinkered.
We added weapons. We removed weapons. Leigh spent ages designing the formation of waves and levels while I changed the code and drew new scenarios, forts and bad guys together with our artist.
We added ‘coins’ you’d collect based on the quality and style of each kill, floating into the corner and accruing with what I hoped was a satisfying ‘clink’ sound as each one landed in your increasing coffers. We even tweaked the physics a bit.
We took it back to the game testing meetup a month later. The reaction was… not good. Well, that’s not true – it was still good, but it wasn’t the overwhelming “dude, you have something addictive here!” we’d gotten the month before.
We removed one of the weapons that we just knew didn’t work. We reverted the physics changes we sensed were the cause of the new hesitance from players… and another month later, we returned with a new suite of changes.
Once again, we got something positive. We were now fairly sure we had the right idea. But we’d now spent a few months on and off it, and it was no longer a ‘tiny, cheap side-project’. We knew we’d spent a bit of cash on it… and the concern became how to make it work. How would we get it to pay for itself?
Monetization: different models even for similar games (told by Leigh)
Our first impulse was to look at a recent Australian success story of Crossy Road. Simple mechanics and a great art style helped it along, but its monetisation strategy was new. It was more than just ‘pay for customization’. Instead, the game asked players to just keep enjoying themselves, rewarding them periodically with one of the dozens and dozens of new avatar types (some of which also re-skinned the environment), and only offering the payments as an optional thing for those who wanted all the characters from the toybox right away.
Of course, it’s gotten much more complex since then, but since we had a variety of weird and wonderful forts available, some of which had a similar image to the avatars in Crossy Road, we reasoned that a relatively simple $1-per-fort arrangement might work for us.
We were very wrong about this. As any developer will tell you, models work for different games for different reasons. We saw the similarities which made it seem like parts of the Crossy Road model might work for us, but the central problem was this: when you’re playing Crossy Road, you’re constantly looking at or very near your avatar – while playing Super Death Fortress you’re looking at the things you’re trying to shoot, and barely ever at the fort itself.
Our first thought was to unlock skins for the enemies you’re destroying, but that didn’t work either. These guys are about as distinct as the lemmings were back in the DOS days.
So we switched it up – the weapons besides your basic mortar (which at this point included dynamite and a carpet bomber) would cost in-game currency. You could buy each at a moment’s notice by tapping on the corresponding weapon icon in the top-left of the screen – and if you didn’t have any ammo, it would automatically spend some hard-earned money on a quick one-off purchase to save your skin when you were being overwhelmed by enemies. But that didn’t really work either…
How to monetize without destroying the game (told by Rohan)
At about this point we had a sit-down with some fellow developers here in Sydney. We let them play the game, then posed the question to them: how would you monetise it, without destroying what the game is?
We got a lot of different responses, but there were three key takeaways:
Firstly: we needed an upgrade-tree (something we already had, at least for each fort) but letting people pay to buy more coins if they didn’t want to just get coins in the traditional way.
This was fine, we figured, as long as we balanced the game in such a way that we didn’t feel we were abusing players. We wanted the game to be playable without paying money. We wanted players to feel (and know) that by playing the game naturally, you could unlock as many of the forts, upgrades and levels as you wanted without meeting one which took so many coins that you just knew you were intended to spend real-world dollars on it.
Secondly: we needed ads. Ads, ads, ads. Everyone told us that anywhere up to 9/10 of their income in free-to-play came from ads. They showed us numbers. They proved their point.
So we included ads – you earned the right to play more by watching an ad every 3-4 rounds. Don’t like that? We added a once-off in-app purchase to remove them forever.
For savvy consumers and lovers of good deals (told by Leigh)
At our next Beer and Pixels playtesting session, we encountered a new frustration – players were enjoying the experience as they had before, but since now the additional weapons were relegated to being attached to specific forts, they had a finite number and no way to unlock more mid-round if they wanted to.
As the golden rule goes – don’t stop your players from doing something they want to do unless it’s going to break the game.
Having more weapons wasn’t going to break the game, but purchasing weapons mid-game was providing more UI challenges than it was solving. Still, explaining this to the playtesters wasn’t helping either. None of them cared what our reasoning was – they just knew they were having less fun. Who were we to deny that?
It was during a conversation with a local community manager and a Twitch streamer that I thought of giving the players a one-off option to buy additional weapons at the start of each round. One of them reported the same problem regarding purchasing additional weapons, but suggested that just doing it on a pause screen would be good.
That, I thought, would break the flow of the game and pull people out of the fun, which we didn’t want, but there was one moment where things weren’t hectic and time wasn’t of the essence: the beginning.
So we added an offer screen which chose randomly from a pre-designed selection of weapons and bonuses and allowed the player to watch an ad OR spend in-game coins to get them. This satisfied the players’ requests, gave them more to spend their in-game coins on (which was key), and also made room for a new simple choice mechanic: smart shopping.
From the design point of view, some of the offer screens give you a very poor deal. Most players will skip this screen or not care how much money they’re spending, but once they’ve become accustomed to how many coins they make in an average game and how many extra coins they might be able to get with one well-placed bomber, they start to get a feel for what a bomber should be worth.
We had our own internal pricing for them, so that they’d be at least a little bit profitable to purchase. But by leaving the player to figure it out for themselves, we gave them a momentary optional cerebral challenge.
If they see an offer come up which charges them 140 coins for 2 bombers and a dynamite, they might know that it’s not a great deal and skip it, feeling like a savvy consumer for seeing the poor value on offer. But if they don’t realise this, they’ll still get the bonus of a bunch of new weapons and will feel good for buying them.
In addition to this, it was the perfect place to put an opt-in ad. We now had the perfect marriage of opt-in ads with a distinct reward for picking them, and unskippable ads every few rounds to monetise those players who wanted nothing more than to keep replaying level one and shooting things (which turned out the majority of the players).
Solution: daily gifts (told by Rohan)
The final monetisation mechanics was about daily gifts. This was one we really should’ve thought of. “You have to keep making your players want to come back,” we were told.
We thought back to early in development, when you could buy new ammunition for special weapons mid-game. Losing that made each game feel a little less unique, somehow.
But offers? Oddly, they fixed it. Every few games you’d get an offer – a selection of power-ups with a coin value attached (and the ability to get them for free by watching an ad). And once per day, your first time playing – you got the good stuff for free.
And that was more or less what we labelled “1.0” and submitted to Apple.
getting the investment back (Leigh)
We received ‘best new game’ placement on the Apple homepages in about 150 countries, so our first week went fairly well. We peaked around 3 days into our 7-day feature, earning our money back from the cost of development in about that time, but then it reduced to a relative trickle.
Interestingly, in our second week we got a placement in the US AppStore (which hadn’t been one of the initial 150 countries, sadly), but it was in ‘action’ games specifically, and didn’t result in much difference in overall daily downloads.
Regardless, that first week let us earn over 100 000 downloads and get our (admittedly minimal) investment in the game back. About three quarters of the revenue has come from ads, and it seems that very few players paid to remove them, even those who did pay to purchase in-game consumable items.
Problem: building the meta-game (told by Rohan)
We’re really happy with Super Death Fortress. Lots of people love the game, declare it addictive and fun, and it hasn’t wasted any money for us. This alone is more than most iOS games can claim, and we’re not going to shrug at it, especially not for our first free-to-play effort.
The game continues to earn money, albeit not huge amounts, and over time it’s fairly certain this will continue to help us stay afloat and work on the usual (bigger, premium) projects.
But the main critical takeaway I have is this: we had a game idea which we ‘knew’ was fun. Our problem was building the game systems – the meta-game – around it to make it work as a product people would pay (through purchases or ad-views) for.
And it mostly worked. But I’ll never stop wondering if there was a better idea we could have come up with than coins, upgrade trees and ad-supported continued play.
It’s the real problem, I guess, with a game prototype that comes before even the slightest concern as to just what kind of game it is, and how you’ll present it to the players.
engage more with the meta-game (told by Leigh)
Our analytics are feeding back useful information about our players. We have high retention, which is key, and a planned post-launch production schedule which includes fortnightly updates – adding stacks of new weapons and forts, as well as an iPad version.
Most of these were already set before 1.0 launched, but it’s interesting to note that in spite of the variety of offers, players simply play level one again and again, enjoying that same thing we did when we first decided to develop the game – flinging a mortar across the screen and blowing up some pixelated bad guys.
I tend to see this as us not having provided enough incentive to engage with our meta-game, and there’s plenty to learn from this for next time.
For now though, the developers say, they’re going to take solace in the relative meagre success of Super Death Fortress and keep figuring out what new updates might enhance the game and make it better.