Small doses of trial and error in video games can be perfectly acceptable, and may even help build tension in certain circumstances -- but lay on too much randomness and the fun can really begin to fall apart. That's not the only kind of trial and error that developers occasionally have to consider. There's behind-the-scenes trial and error too, the kind that inevitably forces studios to dig in and start fiddling around with numbers until everything begins working as it should. Here, I present to you both sides of the coin. While the newly-formed Loveshack Entertainment attempts to deal with potential random user behavior in its upcoming mobile game Framed, Peter Angstadt of Turtle-Sandbox discovers that using examples from similar games in the same genre can work wonders for pinpointing the exact numbers you're looking for.

Framed: How do you steer players away from random choices?

Loveshack Entertainment is a new Australian indie studio, comprised of three industry veterans: Joshua Boggs, Adrian Moore and Ollie Browne. Between the three of them, they've worked on titles like Populous, Theme Hospital, Syndicate Wars, and the Real Racing series. The team's first game, Framed, is due for release later this year on PC and tablets, and has received funding from both Screen Australia and Film Victoria. The game's concept came from the idea that the context in which actions occur is more important and interesting than the actual actions themselves. Indeed, as you begin to swap panels in a chapter on Framed, the story that plays out takes completely different avenues, and can completely turn the tale on its head. Loveshack says that it hopes this angle will allows players to explore the story, rather than feel like they're being beaten over the head with it. But here's the catch: Won't players simply begin throwing the panels around in frustration when they can't find the solution, and keep chopping and changing until the solution is found? "This is something we've been aware of since the beginning," answers Joshua Boggs, Loveshack's coder. "We have really focused on it by making each panel have a clearly defined action, whose meaning is changed by the context it's happening in." In fact, Loveshack has been prototyping its levels on paper cutouts before going ahead with the implmentation, simply to make sure that they all logically fit together and don't require random swapping. "This has helped guide people to logically 'fill in the gaps' in their imagination as the game plays out," he adds. But then there's the flipside of this tale of trial and error: Players will actually want to be a bit random here and there, because there are numerous bad endings for each chapter to be found. So to summarize the situation, Framed needs to be logical enough that a player will be able to find the solution without using too much trial and error -- but will also need to be compatible with trial and error, such that players can have a mess around with it and get fun results out of it. As you'd expect this is "one of our largest challenges," says Boggs. "We have a number of ideas and we're testing some of them right now," adds Adrian Moore, one of Loveshack's designers. "We absolutely do not want the game to be a trial-and-error fest, however captivating the game's story is." One idea that Loveshack has been playing around with to tie all this messy business together, is breaking through the fourth wall -- that is, making the protagonist aware that he is in a video game, and is being subjected to unimaginable pain and death over and over again. At this point, he'll respond to the progression by giving players a bit of a nudge as to how a barrier could be solved. This is just one idea of many that the studio is exploring, artist Ollie Browne told me, which gives you a real sense of how notable an issue trial and error can present.

Cannon Brawl: How long do you make a player wait?

Now to the other side of the trial and error coin. Cannon Brawl is an upcoming 2D side-scrolling strategy game, that pits two players against each other on destructible terrain. Each player has an airship and a base, and must place offensive and defense towers down on the land in a bid to shield themselves, then rain terror down on the opposition. An alpha build on the game is currently available to grab, and I highly recommend doing so. A prototype for the game called Dstroyd originally won the Activision Independent Games Competition back in 2011. Where trial and error comes into play in Cannon Brawl is not at the hands of the players, but rather, in those of the developer. Each of the towers in the game enters a cooldown period after use, and determining how long that should be for each given type was a bit of a nightmare. "At first I was guessing for all those numbers and quite frankly floundering," admits designer Peter Angstadt. "The pacing felt weird, there were times when you were waiting a long time for money or cool down timers, and other times when there was far too much to do at once." It was Angstadt's friend Jeff Gates who suggested attempting to make sure that a player always have an action to perform every two to five seconds, such that it feels like there's always something happening, and you're always kept on your toes. Gates also suggested that Angstadt should take a look at successful RTS games, and analyse exactly how they handle it. "At one point I was recording the average time between available actions in the opening minutes of a Starcraft match and a level of Plants vs. Zombies," he laughs. "This got us to some workable numbers much quicker, but of course there's still lots of trial and error after that." And even once you're close to having figures that work for one part of the game, there's the issue of pacing. Each level should start off relatively calm, then get a bit more pumped up, and finish on a big exciting high. If you've got the same numbers grinding through the system at all times, it's difficult for this effect to be achieved. "It's a design problem where you just need to play the game, make small changes, play some more, and eventually you'll start creeping in the right direction," adds Angstadt. "It can be really tricky because even the smallest change can have a cascading effects that throws the pacing completely off." "For example I slightly increased the range of our basic cannon, which allowed people to hit more targets without upgrading. Players then didn't feel the need to upgrade the cannon, which caused big slowdowns in the mid and end game because the most basic cannon can't do enough damage to overtake the opposing player's ability to rebuild." The incremental changes to combat had another factor to keep in consideration too -- the destructible terrain. As a result of players being able to destroy absolutely any land they please, this meant that many "edge" cases needed to be considered. "Missiles explode when they hit terrain, but sometimes a big missile would explode after hitting a tiny speck of land which is really frustrating," he explains. "I ended up writing special checking code so that tiny specks of terrain don't stop missiles." Adds Angstadt, "The trickiest element so far (and one I haven't solved yet) is getting the AI to be smart about using the destructible terrain to drop your buildings to their doom or to pick shot angles that aren't going to be blocked by terrain."

Overcoming trial and error with a heavy dose of trial and error

As it turns out, in both scenarios a bit of trial and error on the developers' part was necessary to make sure that the game is carried out smoothly for players. "I had this idea stuck in my head for quite a while, and struggled to find a mechanic that would let this idea naturally and intuitively flourish," notes Loveshack's Boggs. Talking it over with his team-mates definitely helped that. "We developed it from there, the three of us prototyping on paper, over several long sessions," adds Browne. "We still prototype on paper now. Little cards we can switch around. It's still not easy but it's a really fun problem to solve." And Cannon Brawl's Angstadt says that he's probably cut as many features and gameplay mechanics from his game as he's added them, simply because he'd find that players would suddenly begin focusing on the wrong part of the action instead. "We tested a feature where your airship had a gun," he notes, "but in playtests people spent the entire time dueling each other in their airships and ignoring all other aspects of the game. There was certainly some fun there, but the pure action gameplay of airship dueling was at odds with our more strategic base building and economy gameplay. It completely unbalanced the RTS aspects so we cut it (although you could probably build a whole new game around airship dueling)!" Whole story elements, such as cutscenes and scripted meetings on the battlefield were also removed as Angstadt came to realize little by little than players simply weren't interested, and felt the story was getting in the way of the gameplay. "Looking back it seems obvious," he says, "but figuring out how much story to tell and how to integrate it smoothly was definitely a learning experience for me." Framed is due for release later this year on PC, Mac and mobile devices, and Cannon Brawl is coming to PC later this year, with potential Mac, Linux and console ports on the way afterwards.