Yesterday I went into detail about specialized interactive items and elements, such as Link's ocarina from Ocarina of Time and the various mini games in the Bioshock series, and when it would be appropriate to implement them in a game. Now I'd like to take a look at successful - and not so successful - implementation in greater detail using Capcom's Okami and Konami's Castlevania: Dawn of Sorrow for examples. (Incidentally, I have zero idea if there's an industry-standard name for these elements, so if anyone knows please clue me in.)
Both games used a specialized interactive item mechanic that amounted to the player drawing shapes on the screen. However, the inputs were not equal in their execution. Both Okami and Dawn of Sorrow were high quality games that were very well received by audiences, but their respective innovative item mechanics could not have been more different in reception. In short, painting with Okami's Celestial Brush was successful, while drawing the magic seals was a “failure”, subjectively speaking. So why did Okami succeed while Dawn of Sorrow failed?
Let's take a look at the Celestial Brush from Okami first.
When the player is granted the Brush early in the game, s/he learns various shapes to draw that interact with the world. Drawing a horizontal line on a monster will slash it, drawing a loop around a tree will revitalize it, and so on. As the game progresses, she learns more and more sigils from gods inspired by the Chinese zodiac, granting more power and more ways to interact with the game world. This interactivity makes the Brush, which is central to the game's plot, a tangible, "real" object that the player connects with and right off the bat provides both agency and approximation.
This value is enhanced further the more sigils the player learns. A sense of accomplishment is imparted when the player is able to recall the right sigil for the right occasion from memory as there are enough discrete sigils to make the brush a versatile tool, but not so many as to break the element of brevity.
The mechanics of painting with the Brush are handled well. The shapes are kept simple, which was essential for the PS2 version of the game which required the player to use the thumbsticks to paint. Additionally, a fair amount of leeway was given in what was considered a "correct" shape: so as long as the player was in the general ballpark the painted sigil gave the desired effect.
Along with the forgiving accuracy, the game pauses all action when the player paints. This time lock allows the player to focus on the task at hand - solving a puzzle or combat in tight quarters - rather than fuss over how accurately one can paint with an input device that is laughably ill-suited for completing the task with any precision (though this is much less the case for the Wii and PS3 Move versions). Since the painting is an overlay on the game screen and is a brief set of actions, it doesn't break the flow.
A time lock isn't an essential requirement - in fact, Bioshock 2's hacking made great use of keeping the hacking action integrated with the in-game action - but generally speaking if your interactive element freezes your character's movement, then the world around him or her should come to a stop as well.
So what about the magic seals?
Dawn of Sorrow’s magic seals seem to hit all the same notes as Okami's brush as they: add to immersion by giving the player a tangible object for interaction with the game world; provide a simple and intuitive interface to work with; challenge the player’s memory to use the right seal at the right time. So why were the magic seals largely regarded as Dawn of Sorrow’s weak point rather than one of it’s strongest features? I think it’s because of two things: the analog nature of human drawing capabilities competing with digital precision, and a too-strict timer for input.
The player is prompted to draw a magic seal on the DS’s touchscreen in order to seal the boss away when the player has reduced the boss monster to zero health. However, human drawing capabilities vary wildly from person to person. While a good programmer will calibrate their system to recognize as much variance as possible as “correct”, it can be a difficult sweet spot to hit between the player having to draw something too precise and just scribbling anything all over the screen. Unfortunately Dawn of Sorrow was a bit too far in the direction of precision, and it was often that a player would draw a seal that would be “correct” to human eyes that the game would reject. While technically the player’s “fault” for not providing the proper input, the perception is instead that the game is being unnecessarily picky, and the player should never feel that the game is at fault.
I think, however, that this is an easy problem to solve: if your input method is something that has to account for a wide range of aptitudes in a subjective skill, then it should focus on a few binary failure/success points while everything else is ignored. For Dawn of Sorrow's seals, each seal has a few points that need to be connected in order, but the shape of the lines connecting them is something the software should disregard entirely. As long as the points are connected in the proper order within the time limit, that's all that matters.
Regarding the timer, once the player is prompted to input a magic seal they have a limited amount of time to do so. This would possibly be less problematic on a console, but on the DS the player has to take their hands off the buttons and control pad in order to pull out the stylus from the back of the handheld console to begin drawing - or just start using their fingers and smudge up the touchscreen. This drastic change in input breaks the flow of the game, and the combination of precise complex input and a strict time limit leads to a lot of errors, particularly with the more complex seals. While overcoming those errors is indeed part of the challenge, the fussiness of the touchscreen combined with an unforgiving time limit often means that errors feel like the fault of the system rather than the fault of the player.
Adding salt to the wound, if the player fails to correctly draw the proper seals within the already strict time limit, the boss monster regains health and the battle picks up again, undoing the player’s hard work. Again, while this is arguably part of the challenge, it easily strays into feeling like penalizing the player for the flaws of the game.
Okami mastered the utilization of a specialized interactive element, and what it had over Dawn of Sorrow was really just one simple thing: allowing for player limitations. It recognized that most people are not going to be good at drawing even simple shapes, much less with a control stick, and gave a wide berth for what it would accept as correct input. It was generous with the time allotted - in fact, there is no time limit on painting - to give the player the chance to be as precise as possible. It was also lenient with the penalties. Whereas a failed seal meant healing a boss for a protracted fight, a failed painting merely resulted in the player immediately trying again. Work with your players' limitations and your specialized interactive element will be an innovation rather than an impediment.