作者：Mathew Kumar

对于Klei Entertainment的Nels Anderson来说，创造一款优秀的潜行电子游戏就等于抛弃许多游戏类型现有的意象。

Anderson是《忍者印记》的首席设计师，这款潜行游戏以其2D卷轴视角区别于传统的同类型游戏。

尽管游戏摒除了《分裂细胞》，《神偷》和《天诛》等游戏中的潜行元素，但仍然是建立在潜行游戏设计的基础上。

Anderson解释道：“我们希望通过《忍者印记》传达给玩家最基本的忍者体验，并确保所有游戏内容都能够支持这一体验。”

在分解了该类型后，Anderson总结了《忍者印记》所具有的5大潜行指南，也就是他所说的“忍者的异端”。而这些“异端”正好打破了潜行游戏设计师之前所列出的种种规则。

异端1：易懂的潜行系统

Anderson说道：“与大多数潜行游戏（即带有明显的仪表之类）不同的是，在《忍者印记》中，光亮与黑暗都具有二元状态。即不管角色是否处于可见的状态，玩家都能够清楚地看到他们——当角色处在黑暗中时便会伴随着闪烁的红光，而当他们处在光亮处时，则会显示出各种颜色。”

这是一种带有暗示的自动应答方法。

“如果你处在警卫视线范围的边缘内，他们便会瞥见你。然后便会毫无预兆地快速冲向你。”

Mark of the Ninja（from gamasutra）

这种二元系统以及屏幕上所呈现出的所有信息——如保镖有限的视线范围，或者在你摧毁一种毁灭性的光速前它的传播范围等，都是为了“创造出容易理解的游戏系统”。

而这么做也都是为了让玩家在采取行动前清楚自己到底会遇到些什么。

“从而让玩家能够将这些元素整合进自己有目的的游戏玩法中。”

异端2：透明的AI

为了推动玩家这种有目的的游戏玩法，我们为游戏中的保镖设定了3种层面的意识，并暗示玩家他们是如何被设置成这些模式，以及在这种模式下他们将会做些什么（游戏邦注：如冲向玩家最后被看到的场所，以幽灵的形式呈现出来，或移动并看向发出声响的区域。）

“这一点主要是用于确保玩家总是能够立即察觉到保镖的行为发生改变。”

异端3：有效的执行

《忍者印记》的开发团队认为，游戏设计不应该违背玩家的意愿。

Anderson以《神偷》系列为例进行说明。他说道：“在《神偷》中，玩家主要是通过魔法箭去影响游戏世界。游戏所提供的魔法箭是有限的，并且如果玩家浪费了一把魔法箭便不能再次使用。重要的是玩家只能通过一个小小的刻度板去瞄准这些箭头，从而说明技能将影响着游戏世界，但这却不是我们想要传达的内容。”

在潜行战术中设置瞄准技能并不是Klei想要采用的方法。Anderson说道：“因为在2D游戏中让玩家瞄准某一对象真的是件非常困难的任务。”

他说道：“在大多数2D射击游戏中，子弹一般都是曳光弹（游戏邦注：一种尾部装有能发光的化学药剂的炮弹或枪弹），在《忍者印记》中，玩家只会想要发射一次子弹（他们扮演着忍者的身份），而如果开发者不能遵循玩家的这种意愿，便有可能摧毁他们想要创造的内容。”

所以游戏便采取了“专注于瞄准对象”的方法，能够完全停止时间，并且不会局限于玩家所拥有的资源中。

但是专注于瞄准对象并不总是最有效的设计功能。Anderson说道：“以前我们便在专注于瞄准对象功能中添加了仪表，但效果却非常糟糕。这么做只会彻底否定整个设计决策；所以有时候我们必须反复检查自己的任何假设。平衡能量并不是一种客观的做法，你真正需要考虑的是如何让玩家做他们想做的事。”

异端4：限制失败结果

Anderson表示，设置远距离的检查点是一种极具风险的设置。

Mark of the Ninja（from gamasutra）

他说道：“这么做真的是太危险了。潜行游戏玩家必须具有非常强大的忍耐性。他们需要不断地等待。如果某一环出现了错误，他们便不得不再次等待，而这就很容易让他们感到厌烦。”如果玩家在某个点上遭遇了失败，他们便不得不重新挑战之前的内容，直到再次到达那个失败点。

Anderson继续说道：“而我们在《忍者印记》的每个有意义的邂逅间都设置了检查点，从而有效地完善了玩家的体验。你应该听过某种情况，即人们创造出某些非常无聊的方法，但却为了不失去工作而硬着头皮继续做下去。玩家亦是如此，他们会为了不浪费最后的6，7分钟游戏时间而继续做一些无聊的挑战。”

但是这并不是说他们完全不能接受失败——失败始终都是合情合理的。尽管Anderson同意失败对于玩家游戏前进的重要影响，但是他也承认在他们的游戏中并不存在哪些功能会突显死亡或失败状态，而这么做比起即时的加载时间更能够带给玩家“正面的影响。”他也表示“如果《超级食肉男孩》或《Trials》让玩家在死亡时还必须盯着加载屏幕，它们便不可能取得成功。”

异端5：避免过于开放的世界设计

Anderson说道：“我们创造了开放世界关卡，但效果却非常糟糕。”

他表示：“我们的大脑并不能直接映射2D空间，”但同时他也承认这一理论并不存在确凿的科学证据。

“在2D世界中我们模拟空间的方式与现实世界并不相同，所以大脑就必须对此进行转化。所以我们很难创建出如3D世界那般巨大的连续空间。”

Anderson声称，2D邂逅空间的有效点便是游戏屏幕尺寸必须朝着任何方向延伸0.5至0.75。但是这么做只会让玩家恍然若失，甚至不能自在地待在这一空间里。如果只是垂直或水平空间的话会更加糟糕。但是当我们着眼于《银河战士》或《恶魔城》时会发现，它们的邂逅空间都非常有效。我想应该是他们发现了人脑中某一奇特的认知方式了吧。

（本文为游戏邦/gamerboom.com编译，拒绝任何不保留版权的转载，如需转载请联系：游戏邦）

Mark of the Ninja’s five stealth design rules

By Mathew Kumar

For Klei Entertainment’s Nels Anderson, making a great stealth action video game meant throwing out a lot of a lot of the genre’s existing tropes.

Anderson was lead designer on Mark of the Ninja, a stealth game that brought an unconventional twist to the genre through its 2D side-scrolling vantage point.

While the game casts aside certain stealth elements laid out by games such as Splinter Cell, Thief and Tenchu, it does still rely heavily on cornerstones of stealth game design.

“With Mark of the Ninja,” Anderson explained, “we wanted to make sure that that the fundamental experience of being a ninja was brought across and everything else supported that.”

After breaking the genre down into its fundamentals, Anderson established Mark of the Ninja’s five stealth guidelines he called the “Heresies of the ninja.” These “heresies” broke the rules laid out by stealth design’s predecessors.

Heresy One: Transparent Stealth System

“In contrast to most stealth games where you have a visibility meter or something like that, in Mark of the Ninja light and darkness are totally binary,” Anderson said. “The way your character looks immediately reveals if you are visible or not – if you are concealed you are in black with red highlights, and in light you are fully colored.”

This on/off approach had one caveat, however.

“If you are at the absolute edge of a guard’s field of vision, they will catch a glimpse of you. They will start to move towards you quickly but not on full alert.”

The binary light system – and the fact that all other information is available on screen, such as the limits of the guard’s field of vision, or the “ring” of how far a sound such as a smashing light will travel before you destroy it, are intended to “make the systems all very, very understandable.”

This intention to visualize exactly what will happen before an action is intended to allow the player to know “full out what will happen before they commit.”

“It allows the player to factor this into their intentional play.”

Heresy Two: Transparent AI

Also in aid of intentional play, the guards have three clear levels of awareness, with cues to how they are set into those modes and what they are doing during them (such as racing to the spot the player was last seen, represented by a ghost, or moving towards and then looking at an area where a sound was heard.)

“The point is to ensure that if a guard’s behavior ever changes, the player will immediately understand what set it off.”

Heresy Three: Narrow gulf of execution

The Mark of the Ninja team felt the game’s design shouldn’t fight against players’ intentions.

Anderson used an example from the Thief series. “The primary was you affect the world in Thief is through magic arrows. You have a limited supply of them and you can’t pick them up again if you waste them. The thing is that the only way you have to aim those arrows is a little tiny reticule, and they’re modelled with physics. So actually becoming skilled to affect the world becomes very satisfying, and was very appropriate to what they were trying to provide in that game, but was absolutely not what we were trying to achieve.”

Placing aiming skill over stealth tactics wasn’t the direction Klei wanted to adopt. One problem was the fact that “2D aiming is actually really god damn hard,” said Anderson.

“In most 2D shooters your previous bullets act as tracer bullets, but in Mark of the Ninja you only want to fire once… the player is a ninja, and if you are constantly bumbling through it kind of undermines the thing we’re going for,” he said.

As a result, the game’s solution was “focus aiming,” which stops time completely and is not limited by the player’s resources.

Focus aiming wasn’t always an unlimited-use design feature. “[Previously], we added a meter [to the focus aiming] and it was just horrible,” Anderson said. “It just completely undercut that whole design decision; sometimes you have to double check your assumptions. Power-balancing is not really objective … you must let players do what they want to do.”

Heresy Four: Limited Consequences for Failure

Anderson said he was wary of using widely-spaced checkpoints “as a means of providing challenge.”

“This kind of difficulty is very, very dangerous,” he said. “In a stealth game people come in with a very patient style of play. There’s a lot of waiting. If something goes wrong and they have to do all that waiting again, it quickly descends into tedium,” he said. If people get through a section of a challenge before failing, they will generally do that section again exactly the same until they reach the point they failed at.

“With Ninja, it basically had a checkpoint between every meaningful encounter,” he said. “This allowed us and the player more experimentation in the game. You’ve all heard of degenerative strategies, where people have worked out one thing that works and it’s boring as hell, but they keep doing it because they don’t want to lose work. They don’t want to lose the last six, seven minutes of play so they just keep doing that boring thing.”

That’s not to say failure states were completely unacceptable — within reason. Although he agreed that it would have a “significant impact on your engineering,” Anderson argued that there is no single feature in a game that features death or failure states that will gain “more positive feeling” than instant load times. He was in fact prepared to argue that “neither Super Meat Boy nor Trials would be as successful as they were if you had to look at a loading screen each time you died.”

Heresy Five: Less-Open World Design

“We made [open world] levels,” Anderson said, “and they were just god damn terrible.”

“Mentally mapping 2D space is really not something our brains are meant to do,” he said, while admitting he had “done no hard science” on this theory.

“In 2D you are simulating a space that’s not the way it would be in reality, so your brain has to perform a translation. There’s a difficulty there so you can’t build a contiguous space nearly as large as you can in 3D.”

Anderson claimed the sweet spot for a 2D encounter space was the game screen size plus “0.5 to 0.75 of a screen in any direction. … Any more than that people start to feel lost or not really competent in that space. A little more if it’s just horizontal or vertical. If you look at a Metroid or Castievania that’s roughly how all of their encounter spaces work. I think that’s because they stumbled upon a weird cognitive way the brain works.” (source:gamasutra)