作者：Josh Bycer

在游戏设计中，我最喜欢的词汇便是随机化。如果能够正确使用，它可以极大地提升游戏的再玩性。诸如《幽浮》和《暗黑破坏神2》之类的经典游戏都绝妙地运用随机化来让玩家不断玩游戏。近期出现的独立游戏，比如《Dungeons of Dredmor》、《Din’s Curse》和《Space Pirates And Zombies》，这些都是可以用来阐述随机化利弊的绝妙例证。

在我们谈论随机化的利弊之前，先分清可以在游戏中执行的随机化程度是很重要的。程度并非以个人偏好来划分，而是设计师使用随机化的方法。

低：装备放置位置和找到它们的可能性。动作RPG游戏通常使用这种程度的随机化。应当注意的是，你可以将重要道具设置在固定的地点，将普通道具和装备随机放置。

中：在低程度的基础上加上敌人位置的随机化。执行这个程度的随机化有两种方法，第一种方法是在游戏中设计“特别”的敌人。在《暗黑破坏神2》中，玩家偶尔会碰到有名字的怪物，这些敌人与其同伴看起来不同，而且名字前有特别的修饰词，比如强攻和火抗等。第二种方法便是随机安放敌人的位置。

高：包含以上两种程度，再加上世界的随机化。rogue-like游戏通常使用这个程度的随机化，但是这个类别并不局限于rogue-like题材游戏。《Space Pirates And Zombies》在游戏开始时允许玩家创造随机的宇宙。诸如《文明》之类的TBS游戏也允许玩家在随机化的世界或预设的地图条件中玩游戏。

现在，让我们谈谈使用随机化的优势所在。首先，随机化是让游戏产生再玩性的绝妙方法。你永远都不知道财宝箱中有什么，下扇门背后会出现什么，这将成为让玩家持续玩游戏的绝佳驱动力。游戏中随机化的元素越多，体验的新鲜感持续时间就越久。

当我同好友谈论起rogue-like游戏时，他认为此类游戏就像是赌博机。从某种程度上来说他的比喻是正确的，你永远都不知道自己是否会有好运获得所有需要的装备，情况也可能对你不利。

随机化还可以用来当作难度调节器，让游戏对新玩家而言是个较小较容易的世界，而对专家级玩家来说可能是个更大且更具挑战性的世界。《Din’s Curse》在这方面做得很好，玩家可以选择敌人的等级、世界的大小等要素。

当然，随机化也存在某些弊端。回到之前那个赌博机的比喻，虽然其奖励充满诱惑力，但是如果失败次数过多会让人们感到很沮丧。在游戏《Dungeons of Dredmor》中玩最高的难度时，因为敌人和装备出现的位置，我有90%的情况在跳下第一层楼之前就失败了。

Dungeons of Dredmor(from downtr.org)

随机化根据其程度深浅，很容易产生让玩家感到别扭的地图。回到《Din’s Curse》这款游戏中，我在游戏中多次碰到地下城入口聚集大量敌人的情况，或者在第一层便遇到名字上有着最强修饰语的BOSS。

其次，构建随机化关卡有可能影响游戏的质量。使用功能和基本资产创造随机化关卡很简单，但是创造出有绝妙视觉效果而且构建精巧的关卡就不那么容易了。

《Demon’s Souls》便是绝佳的例证，虽然你可以看到随机化关卡对游戏大有帮助，但是也必须承认其关卡是精心设计的结果。每个关卡都有着独特的挑战和风格，足见设计师花费了大量的精力来设计关卡。

我要提的首个随机化关卡的不良例证便是《Phantasy Star Online》。在这款游戏中，每个地下城的布局都是随机的，但是游戏中的每个世界都只有几个空间。这意味着每层或许有4个不同的空间模型，而这就是游戏的全部。关卡设计完全是自毁式的，让人感觉像是将各种元素拼凑起来。这也是我们在创造随机化关卡时需要避免的事情，游戏世界的设置需要某种程度的凝聚力。《Dungeons of Dredmor》的首款零售版本有展示房间样式的地图，这从某种程度上降低了游戏的质量。

第二个问题在于，你需要考虑的游戏机制越多，创造出像样的系统就越难。原因在于，玩家接触到的机制越多，需要编程和执行到引擎中的变量也就越多。在《Mine Craft》中，每次新游戏时都会产生随机化的世界，而这种做法之所以能够产生效果，其原因在与玩家只能通过方块与游戏进行互动。

假设有人为《杀出重围：人类革命》设计随机化关卡，要让关卡能够得以运转，引擎必须能够创造出随机化场景，允许玩法风格的改变，这就意味着关卡中必须有可以打破的墙体以及可以到达的区域。如果关卡中没有这些元素或者不允许其呈现游戏进展，玩家会因这种无法自行构建的关卡而感到沮丧。

要创造出能够发挥作用的随机化系统，就必须将其构建在线性的层次之上。这意味着，对于每个随机化元素而言，都必须有某些担保的东西。比如在《Dungeons of Dredmor》中，虽然游戏世界每次都具有随机化特点，但是每层的敌人样式基本都受到限制。你永远都不会在第1层碰到本该在第5层看到的敌人，反之亦然。

《Din’s Curse》的设计同样也是如此，每层中都有条向上的路和传回城镇的入口。就敌人而言，以玩家在生成世界时选择的初始关卡为基础，敌人会随着玩家在地下城中的探索逐渐变强。

再来看看《Mine Craft》，虽然世界的创造是完全随机的，但是每个新世界中都有着相同的基本规则：更深的地下能发现更好的资源，敌人在黑夜里生成，玩家可以自由前往所有的地方。有了这三个常量，玩家仍然可以在随机化的范围内体验每次游戏带来的新鲜感。

我希望能够在随机化的世界中体验游戏，无论玩家身处何处，游戏世界都应该围绕这个位置来构建。较难的地方离玩家较远，较容易的地方离玩家较近。大部分的建筑都是随机化的，但某些类似于地下城的特殊建筑则采用线性设计。这会让玩家获得不同的游戏体验，但是仍然有其中获得进步的感觉。

设计精巧的随机化系统可以提升你的游戏设计，给玩家增添额外的价值。但是，就像所有优秀机制一样，只有正确的设计和执行方式才能诞生理想的随机化效果。（本文为游戏邦/gamerboom.com编译，如需转载请联系：游戏邦）

Random Thoughts on Randomization in Game Design

Josh Bycer

When it comes to game design, randomization is one of my favorite words. When used properly, it enhances a game’s replay-ability dramatically. Classic titles like X-Com and Diablo 2 make excellent use of randomization to keep gamers playing, and the rogue-like genre is famous for its use of randomization. Recent indie titles:

Dungeons of Dredmor, Din’s Curse and Space Pirates And Zombies each use randomization and are examples of the pros and cons of it.

Before we talk about the pros and cons of randomization, it’s important to define the degrees of randomization that can be implemented in a game. The degrees are not ranked in terms of preference, but just the ways that a designer can have randomization.

Low: Just equipment placement and probability of finding them. Action RPGs usually have this degree of randomization. Note, you can still have important items in set locations and have common items and equipment randomized.

Medium: Enemy placement along with the low category. There are two ways of implementing this, first is with having “unique” enemies. In Diablo 2, there was a chance of running across an enemy who had a name, these enemies looked different from their cohorts and had a unique modifier such as: increase damage, fire resistance, etc, and the other way is randomizing enemy positions as well.

High: Everything in the last two categories, along with world randomization. Rogue-likes fit the bill here, but this category is not mutually exclusive to rogue-likes. Space Pirates And Zombies allows players to create a random Universe from the get-go. TBS games like Civilization also allow players a chance to play on a randomized world, or preset map conditions.

With that out of the way, let’s move on to the pros of randomization. First, is that randomization is a great way to have replay-ability in your game. You’ll never know what that treasure chest will have, or what is behind the next door, and that can be an excellent motivator to keep playing. The more elements that are randomized in the game, the longer the experience will stay fresh.

While talking to a friend about Rogue-likes he told me that to him, they were like a slot-machine. In a way he is right with that analogy, you never know if you’re going to get lucky and get all the equipment you need and blaze through the game, or if the odds are going to be stacked against you.

Randomization can also be used as a difficulty modifier, allowing the game to generate a smaller or easier world for newcomers, or a larger more challenging world for experts. This is something that Din’s Curse does well, as players can choose the levels of the enemies, how big the world is, among other factors.

With that said, there are some cons to randomization. Going back to the slot machine analogy, while the lure of a jackpot can be motivating, losing thirty times before you get there can be demoralizing. In Dungeons of Dredmor, playing the game at the hardest difficulty setting, it felt like 9 out of my 10 runs ended before I even got off the first floor due to unlucky enemy and equipment placement.

Depending on the degree of randomization, it’s very easy to generate maps that completely screw the player. Going back to Din’s Curse, there were plenty of times that the game spawns hordes of enemies at the entrance to the dungeon that overwhelmed me or having a boss appearing on the very first floor with the hardest modifiers attached to it. Din’s Curse also features modifiers to the world that makes things harder; getting stuck with the worse modifiers at the beginning can be a big hole for the player to crawl out of.

Next, is that when it comes to randomized levels, most often quality takes a hit. Creating a randomize level using functions and basic assets is easy, creating a level that not only looks aesthetically pleasing and is crafted well is another story.

The perfect example of this would be Demon’s Souls, while you could argue that randomized levels would have helped the game, no one can say that the levels weren’t carefully designed. Each level was developed with a specific challenge in mind to the point that each level had its own mood and style. From the vertigo inducing heights of stage 3-2, to the poison gauntlet of 5-2, you could tell that the designers went to great effort to design the levels.

The first poor example that I had with randomized levels was with Phantasy Star Online for the Dreamcast. In the game, every dungeon’s layout was randomized, but the game only had a few room assets per world. What this meant was that every floor had maybe 4 different room models and that’s it. The level design had a very “Frankenstein” feel, in the way that the level design felt like it was just stitched together from various elements. That is also something you want to avoid when creating randomized levels as there should be a sense of cohesion in how the world is set up. The first retail build for Dungeons of Dredmor had door assets show up where rooms were supposed to be, and it brought the quality down somewhat.

The second problem is that the more game mechanics you have in mind, the harder it will be to create a decent system. The reason is that, the more mechanics the player has access to, the more variables will have to be programmed and implemented into the engine. In Mine Craft, on each new game, the world is randomly generated for scratch and it works because the only interactions the player has is putting a block down, interacting with objects and attacking.

Let’s say that someone designs a randomized level for Deus Ex: Human Revolution, in order for that level to work, the engine must be able to create a randomized setting that must also allow for the variations in play-style, meaning it must have breakable walls, vents, areas to reach and terminals to hack. If it doesn’t have all these elements and have them presented in a way that allows progress, then players will become very frustrated if the game gives them a level with a solution that is impossible for their build.

To create a randomized system that works, it has to be built on top of a layer of linearity. What that means, is that for every random element, there must be something guaranteed. For example, in Dungeons of Dredmor, while the world is randomized each time, enemy types are limited for the most part, to specific floors. You will never see an enemy who appears on floor 5, on floor 1 and vice versa.

Same goes for Din’s Curse, on every floor no matter what; there will be a way up, along with a portal back to town. In terms of enemies, the enemies will progressively get stronger the further the player descends into the dungeon based on what level the player set as the starting level at world generation.

Going back to Mine Craft, while the world is completely randomized at creation, the same basic rules apply to each new world: better materials are found deeper underground, enemies spawn in darkness and the player has complete freedom of where to go. With these three constants, the player still experiences the world fresh each time due to the scale of the randomization.

For one of my game ideas I envisioned the game taking place in a randomized world. Where ever the player is placed, the world will be built in a sense around that position. Incredibly dangerous areas would be further away, while easier areas will be closer. The majority of the buildings will be randomized, while special buildings that act more like dungeons are linear in their design. This will allow players to experience the game differently each time, but still have a sense of progression that they can base their play through on.

A well designed randomization system can be the cherry on top for your game design, giving players added value. However, like all good mechanics, it must be properly designed and implemented. (Source: Gamasutra)