作者：John Harris

本篇专栏是关于两种最常见的类别：药剂和卷轴中最受欢迎的道具的深入讨论，我们将其归为能够使用并购买的“一次使用”道具。

在一个充满怪物的地牢中探索并不是一种健康的活动。如果游戏只是关于四处游览，划定区域并让玩家在遭遇不可避免的死亡前杀死怪物，那么这只能说是一种有趣的简单游戏，但却不具备闪光点。除非游戏能够让玩家在探索中获得某些内容，也就是珍宝。

珍宝总是会指引着玩家走向更加危险的处境。就像在大多数roguelikes游戏中，珍宝总是隐藏在地牢中。有时候珍宝是指食物，游戏要求玩家寻找更多珍宝是为了阻止他们在较简单的场景中无限制了提升级别，也就是在这种情况下，真正有益的珍宝是那些能够打击玩家的内容。与如今的大多数角色扮演游戏不同（即装备很大程度决定着玩家的能量），在roguelikes游戏中，装备影响着玩家的体验，并且属于随机生成内容。

为什么要添加珍宝

为什么玩家会因为找到珍宝而感到满足？我们必须承认，如果缺少了珍宝，许多roguelikes游戏将失去许多乐趣。我认为玩家之所以希望能够在自己所探索的危险区域中寻找珍宝或其它有价值内容是受到人类早前部落文明的影响。好像有点离题了。

随机生成的珍宝便是roguelike游戏中最大的不规则元素。怪物是随机的，但是至少在每个关卡是基于同一比例而出现；地牢是随机的，但是与陷阱一样大多数时间都会呈现在地图上。而只有珍宝能够彻底改变游戏，并且它们所呈现出的不同能量将相互影响，并与怪物和地牢一起而创造出完全不同的roguelike游戏。

在给予玩家各种珍宝时时开发者需要思考如何设定珍宝的价值。如果珍宝不够强大，玩家便会认为没有寻找的必要；而如果珍宝太过强大，游戏便很容易失衡，即珍宝将变成是最后决定玩家成功的主要元素，而不是技能。我们可以从角色扮演游戏的来源，即奇幻文学作品中去设定珍宝。例如在《哈比人历险记》后半部分中，主角Bilbo便依靠魔戒度过了许多危险处境。而《指环王》最终明确了这枚魔戒的真正作用，并且书本中的其他角色也能像Bilbo那样感受到魔戒的能量。他们认为魔戒的能量远不止表面上所看到的那样。因为Bilbo是依靠自己的聪明才智找到魔戒，所以他拥有这种想法也是理所当然。但是即使拥有魔戒，Bilbo也会深陷陷阱，并需要巧妙使用魔戒才有可能逃离危险。换句话说，Bilbo拥有魔戒正是其智慧的体现。所以设计师，创造者和游戏世界的管理者就需要想办法进行适当设置，让玩家也可以凭借自己的聪明才智在roguelike游戏中寻找珍宝。

我们已经概括了roguelike游戏中一些主要的珍宝类型。有趣的是，尽管《Rogue》已经诞生了20多年之久，但是游戏中的主要道具类型仍然被广泛应用于近乎所有的roguelike游戏中。这是首次用于详细阐述这些道具的专栏文章。而在第一部分中，我们将先说说一次使用道具，也就是那些使用一次后便可被丢弃的道具。

一次性魔法：一次使用道具

除了食物，一次使用道具类型主要分为药剂和卷轴。有些游戏也会提供随机的食物，如浆果类和蘑菇等。《Shiren》便提供了草药，即食用时具有一定的营养价值，但通常情况下其功能更像是药剂。《ADOM》也具有独特的草药，即它们的功能并不是随机生成的，但在不同游戏中却都保持着相同的功效。（《ADOM》的草药还拥有其它独特且有趣的属性。这是我在这款游戏中最喜欢的元素之一，但是它们却不适用于普通的roguelike游戏类别中。）

在标准的roguelike游戏中，随机生成的一次性道具是最难识别的道具之一。识别一次性道具所存在的最大问题便是，当这些道具消失后，它便不可能再出现。玩家只有一次机会去摸清楚道具的用途。并且有些道具只能在特定情境中发挥功效，所以如果玩家能够在适当时候，或者有所准备地使用这些道具，它们便能够发挥最大功效。当然也有些一次使用道具会带给玩家不必要的麻烦，如《Rogue》的失明药剂——如果玩家不能在适当时机使用该道具便会因此输掉整盘游戏。

许多游戏还包含了自动识别药剂和卷轴，但是《Rogue》和《Hacks》却并未如此。这两款游戏都要求道具必须在自动识别前清楚地呈现给玩家其效果和用途。有些道具的效果并不明显，所以玩家只能凭借经验或购买识别卷轴为其命名。有些道具只会在特定时候发挥作用（如侦查卷轴只会在有侦查任务时才显现），也有些道具只会在特定情境下给予玩家临时的提示。

药剂所具有的一次使用属性也是roguelikes游戏区别于经典的《龙与地下城》游戏的一大元素。《OD&D》以及第一版的《AD&D》便陈述了一些我们并不熟悉的魔法道具，而因为药剂具有气味，所以玩家可以无需消费便将其识别出来。在某些游戏中，药剂具有各种各样的功效，就像有些液体药剂并不能饮用，而是用于某些特定对象或玩家的皮肤上，甚至有时候只要打开瓶塞便能发挥作用。经典的roguelike游戏主要是受到像《D&D》等游戏的启发，而《Rogue》和《Hack》这类型的游戏则与之不同，即游戏中的药剂都不是用于饮用。就像在《Rogue》和《Nethack》中，玩家将道具扔向怪物便能够抵消掉“糟糕”道具的破坏性。如在《Rogue》中，这么做将会沉重打击怪物，而在《Nethack》中，扔掉的药剂将能阻挡怪物的靠近，造成一种“烟雾效果”。《Nethack》还让玩家能够将道具浸在药剂中或将其混合，并且不管玩家做出何种选择都是具有战略价值。这两款游戏也都包含“恐吓怪物卷轴”，即扔在地上便可生效。但是尽管如此，大多数游戏中的药剂仍然是用来饮用的。

我们还能在游戏中找到许多一次使用道具，并且与随机生成的佩戴物（如戒指或项链）不同的是，玩家总能在此够获得各种使用提示，所以这时候识别卷轴便很难派上用场。更重要的是，识别卷轴在大多数游戏中都属于随机生成的一次使用道具。在许多游戏中，玩家可以使用试错法去识别某些道具。支持商店销售的游戏总是会提供给店主一些识别暗示，也就是所谓的“价格ID”。在不同游戏中这种策略的功效也有所不同，就像在《Nethack》中它便导致游戏失去了平衡，而在《Shiren》最后的地牢中却非常有效。因为这种方法能够缩减对象功能从而避免耗尽玩家的道具，或要求玩家具备一定的识别卷轴知识，所以当玩家基于这种方法去使用一次使用道具时便能够发挥巨大的功效。

这两种类别具有何种功能差异性？

比起仍卷轴，扔药剂更能发挥功效。据我所了解唯一能够呈现出扔掉卷轴并产生效果的游戏只有《Shiren the Wanderer》。

从根本上来看，药剂也就是化学药品，而有用的非魔法药剂的功效也优于卷轴。对于某些游戏来说这便是一大差异性：魔法药剂是否能够侦查到油瓶的位置？就像在《Nethack》中，最有用的药剂便是水。《ADOM》中亦是如此。

除此之外，药剂总是比卷轴更加万能。玩家还可以将道具浸在药剂中，或将其混合在一起。《Nethack》便根据类型将硬用硬编码药剂与结合混合在一起。“Color Alchemy”能够掩盖随机的药剂结果，并根据药剂颜色和扣除色将其混合在一起。《ADOM》非常重视其“炼金术”系统，并在游戏一开始便定义了一系列随机的混合“食谱”，让玩家能够在提升“炼金术”技能后掌握这些“食谱”。

卷轴拥有各种各样功效，而药剂则总是作用于对象的外观上。同时我们还需要注意的是，在同一款游戏中，卷轴和药剂也能呈现出侦查效果。（就像《D&D》中的一系列药剂便能够控制各种类型的生物。但是前提是玩家必须饮用了这些药剂，它们才能透过饮用者发挥作用。）

如果效果要求玩家输入更多内容，特别是选择某一道具，这一道具必然就是卷轴。

以下是各种类型的游戏中最引人注目的道具——药剂和卷轴，及其有趣的属性。

药剂

治疗（额外/完全治愈，治疗轻度/中度/严重的伤处等等）

除了武器，治疗药剂应该是所有roguelike游戏中最常见的道具。尽管大多数roguelike角色都能够快速被治愈（即在最多100次的休息后便能恢复最大生命值），但是不管是同时面对多个对手还是遭遇非常强大的怪物，他们都需要一种能够帮助自己快速恢复能量的方法。

在这些游戏中最有趣的选择便是能够帮助玩家获得最大生命值的治疗药剂。如果玩家在完全健康时饮用这一药剂，他便能够获得最大生命值的提高。也就是玩家可以一开始便有效利用这些药剂，因为在大多数游戏中，玩家获得最大生命值的主要方法都是获得经验级别，但这却是一个非常复杂的目标，并且最佳行动也是取决于玩家所处的情境。效果较弱的药剂只能帮助玩家恢复最大生命值——特别是在游戏最后，而较强的药剂却能在任何时候派上用场，例如当玩家在逃离强大的敌人时。关于这种药剂的另外一种使用方法便是立即减轻某种状态效果，如困惑或中毒。而更强大的药剂类型则能治愈更多类型的疾病。这种功效在《Nethack》中非常重要，特别是当玩家面对某些罕见，并且非常危险的情境时。

提供给玩家大量的治疗药剂并不会对游戏设计造成多大影响。在玩家要求使用药剂后，远比他们强大的敌人总是能够凭借进一步攻击而再一次重创玩家。《Shiren the Wanderer》便拥有一种道具——“Chiropractic Jar”能够马上治愈玩家并恢复其各种病状。尽管这些道具并不罕见，并且玩家也可以花钱去购得它们，但是玩家仍然会在游戏中感受到压力。因为他们必须挪出时间并谨慎地使用这种道具；并且尽管这一道具并不罕见，但也属于有限的资源，所以玩家必须保守地使用。并且只有具有这种约束才能保持游戏的平衡。

恢复能力

《D&D》的6大属性中唯一能够变成《Rogue》的便是力量，即影响着玩家带给怪物的伤害。游戏一开始玩家的分数为16，并且玩家对于“最大力量”的探索也是从16开始。游戏中所包含的各种怪物，陷阱和道具都将削弱玩家的力量，除了最大力量。但是与生命值不同的是，力量并不会随着时间的发展而恢复。就像在《Rogue》中，只有用于恢复能力的药剂能够将力量恢复至最高值，并挽回其中的损失。

与损失盔甲值一样，力量损失的风险也是局限于地牢中的某些范围内，如遭遇响尾蛇。《Rogue》的视线规则（游戏邦注：即在走廊和暗室中我们只能看到玩家周边的空间）表明，玩家在某些时候将难以避免怪物的进攻，也就是说这时候遭遇力量损失也是不可避免的事。所以恢复能量药剂就变得更加重要。

我所说的“最强大的”力量其实是指玩家当前的最大能力，也就是在恢复所有遭遇损失的属性后的状态。虽然其它roguelike游戏总是能够提供更多统计数据，并呈现出各种不同的功能，但是从根本上来看它们只是在沿用《Rogue》的能力恢复药剂。

增加力量

在《Rogue》，增加力量的药剂将能够提高玩家的力量值。如果增加后的力量值等于最高值，它们便都可以获得一个点的提高。而如果玩家遭遇过力量损失，他便只能恢复一个点的力量值。

也就意味着如果玩家的力量值在之后出现下降，那么引用恢复能力的药剂将能够帮助他们从新恢复到新的最高值。而因为拥有较高的力量具有绝对的优势，所以玩家有必要在处于最高力量时保留增加力量药剂。

但是这两种道具都难以避免力量的损失。在游戏过程中，大多数角色至少会遭遇一点力量损失。它们均属于随机生成药剂；所以玩家有可能在游戏中遇到两种药剂均未出现的情况。如果玩家的力量开始下滑，但他又找不到恢复能力的药剂，他是应该喝下增加力量药剂去提升一点已损失的力量还是继续寻找恢复能力药剂？我们需要记住的是，玩家并不知道哪种药剂会最先出现，并且他们会频繁遇到各种能够吞噬他们力量的毒药。这是roguelike游戏中很常见的选择。

《ADOM》拥有大多数roguelike游戏中最发达的统计系统。就像《D&D》拥有6个统计系统；而《ADOM》则拥有9个，并且提供了一些独特的药剂去完善这些系统——例如有些药剂能够暂时提升玩家的力量，或者有些药剂只能提高最大力量。（同时还包含了邪恶的互换药剂。如果玩家不能谨慎使用这种方法便有可能因为误喝了某些错误的药剂而致命。）除此之外还包含了增加属性的药剂——较为普遍但却不能提高最大力量。特别需要注意的是：《ADOM》的系统并未限制最高的统计值，但是在上升过程中玩家将会发现很难继续进行提升。

获得级别

对于玩家来说另外一大难以作出的选择便是何时喝下获得级别的药剂。

在角色扮演游戏中，玩家必须快速获得更多经验值才能提升经验级别。而有些游戏，如早前的《D&D》便使用了双倍级数的方法。的确，玩家需要使用更多经验值去对付更加强大的怪物，但是许多roguelike游戏却不能在这点上保持同步，也就是玩家的级别提升速度非常缓慢。特别是在《Rogue》中，怪物的难度系数的提升总是远远快于玩家能力的提升。也就是当玩家越深入游戏时，他们便会遭遇更大的危险，但是经验级别仍在慢慢累积着。

毒药（疾病）

这是一种糟糕的道具，并不存在正面的主要目的。但是几乎所有的roguelike游戏的道具都具有次要目的，例如玩家可以将这种药剂扔向敌人。即使是最糟糕的道具也能够发挥积极的功效。但是如果基于最平常的方法去使用这种药剂，也就是饮用，玩家便会因此遭遇不幸。

我们需要注意的是，毒药本身并不能让玩家致命。但是因为在游戏中玩家需要通过使用去识别任何事物，所以这便是最大的禁忌。也就是如果玩家必须使用任何未知的事物，那么这些药剂将会让他们立即致命！这并不意味着使用道具便能够帮助玩家避免死亡——如果玩家当前的状态很糟糕（如喝毒药而降低了自己的力量），或道具的使用方法并不是基于标准的方式（使用死神魔杖击中自己），或道具非常稀有（如当玩家在《Nethack》中带上护身符后，便能够通过祈祷而幸存下来。）。道具并不能永远支撑着一款游戏的发展。就像在《Rogue》中，最糟糕的一次使用道具是失明药剂，而最持久的药剂甚至能够掩盖游戏中小部分的空间视觉范围，但却也会在上百次使用后功能消退。

侦查

显然对于现玩家来说这并不是一种有效的方法，但是在roguelike游戏中，侦查却是最有用的对象之一。怪物侦查让玩家能够选择打斗方式，道具侦查让玩家能够决定探索方向，地图侦查能够向他们知名最佳逃离路线。我们还需要清楚，侦查其实是介于药剂和卷轴之间的灰色地带，不同的游戏将把这种功效分配到不同的类别中。而《Rogue》则同时具有这两种类型的侦查！即食物侦查就是卷轴，而魔法和怪物侦查则是药剂。

困惑，失明，麻痹

如果玩家喝下这些药剂那就糟糕了，而如果是将其投向怪物便能扭转局面。所以说“糟糕”是相对于情境而言；就像在《Rogue》中，如果玩家进入了Medusa楼层，失明药剂便会转弊为利。

这些药剂主要是作为一种识别衬托，即在玩家使用某些事物中添加风险性，或创造出随机的药剂而让玩家在危险的时刻将其喝下。这时候玩家便能轻松地识别出一次使用道具。

止渴（水，圣水和邪恶之水）

《Rogue》的每一种道具类别中总是包含了一些无用的道具，从而否定了那些认为所有的道具都具有功能的看法。就像卷轴类别中的白纸和药剂中的止渴道具。除此之外还有无法力的魔杖和装饰用的戒指等。值得注意的是《Nethack》虽然也包含了这些道具，但却赋予了其特殊的用途。

卷轴

识别

继治疗后，识别卷轴应该算是最常见的roguelike道具。在许多游戏中它们还是最常生成的道具。

虽然识别卷轴很常见，我也意识到没有一款roguelike游戏会故意识别错某些内容。《Nethack》中受诅咒的识别卷轴便只能识别少数道具，并且不会欺骗玩家。而《D&D》则包含一些表面是有用的危险对象，如能够让人产生错觉的邪恶药剂，从而引起DM欺骗玩家他们的角色所面临的处境。Roguelike游戏虽然带有某些狡猾的设定，但却不会做得太过火。

迷惑武器/盔甲

这些道具可以说是卷轴版本的增加力量药剂。药剂可以通过提升玩家的物理攻击奖励去提高他们应对危险的能力。而卷轴则是通过提高武器的攻击奖励并降低敌人的击中率，或者让玩家使用某一特殊设备去度过危险。

这些道具都能无限期地改善玩家的状态。它们并不存在期满之说，但却会因为敌人的进攻，糟糕的使用或陷阱等失去功效。这也让这些道具变得更加有用。尽管在单一的遭遇中，单一的奖励点并不具备多大的功效，但是随着时间的发展，这种效益将越发明显。如果玩家足够幸运，也就是能够轻松地找到这些道具，游戏便会变得更加简单。所以大多数游戏都会通过限制力量的强度或道具的功效去阻止这种情况的发生。但这却不是一种有效的方法，如果只是因为设计师不希望玩家变得过于强大而如此设定，所有道具便会很快失去功效。

特别需要注意的是，在《Rogue》中，迷惑武器卷轴相对特别，因为它能够提高武器两种状态中的一种——即击中和损害，而卷轴将随机决定哪种价值得到提高。有一些模仿《Rogue》的游戏将迷惑武器分割成两种不同的道具，也有一些游戏将武器和盔甲卷轴整合成单一的“魔法”卷轴，让玩家能够根据道具的能量做出选择。

在大多数roguelike游戏中，这些卷轴的功能只有在相关的道具处于使用状态时才能发挥功效。如果武器或盔甲都未投入使用，这些卷轴的功效就被白白浪费了。就像《Nethack》将其当成是一种陷阱；在游戏中最糟糕的卷轴便是破坏盔甲。如果你了解了某一不知名的卷轴，你便会想穿上盔甲去利用不知名的迷惑盔甲卷轴。但是如果这时候卷轴被替换成破坏盔甲呢？其它游戏使用的另一种陷阱是，使用一种卷轴让玩家去运行某一道具，但却不告诉他们为什么要这么做。

作为一种额外能力，这些卷轴能够脱离其所运行的道具。

Vorpalize武器

“Vorpalize”指的是什么？不管我们从电子游戏中领悟到什么，“vorpal”都是一个没有实际意义的词。关于该词的使用我们可以追溯到Lewis Carroll所写的《Jabberwocky》（游戏邦注：Jabberwocky在英语中就是“无意义的文字游戏”的意思），主要用于形容一把剑，并且在联系上下文后便能够发现其内在意义。角色扮演游戏便经常使用这种方法，尽管对于许多内容并不存在一致的定义。

《Rogue》包含了名为Vorpalize武器的卷轴。当玩家阅读该卷轴时，他们的武器便会暂时闪烁出光芒。这主要用于赋予武器法力，并在游戏中选择一种怪物成为武器的目标敌人。如此当玩家攻击这类型怪物时便能立即让它们毙命。不过这种卷轴也存在缺陷，即玩家并不能在同一种武器上使用两次Vorpalize卷轴。

这么做是为了惩罚过于贪婪的玩家。当然了，玩家只有在丢掉武器后才知道贪婪的底限。这是玩家在游戏过程中需要学会的另外一大要点，这也是帮助他们取得最终胜利的重要元素。也正因为如此，《Rogue》才能长久吸引玩家的注意力。

《Nethack》会在武器或盔甲过于强大时摧毁它们。当一种武器的魔法已经超过其安全限制，它便会发出警告式的震动。法力越高也就意味着该武器被摧毁的可能性越大。

混淆怪物

对于新玩家来说，这应该是《Rogue》中最神秘的道具。在感受到直接效果后，玩家的手将开始变红。而他们接下来攻击的怪物将暂时变得糊涂。实际上这是一种很强大的道具，尽管在战斗前阅读这种卷轴有可能让玩家将其浪费在较弱的怪物身上。

威吓怪物

这是游戏中最神秘的道具之一（前提是玩家并不知道其秘密）。这是唯一一种无需拾起便能够识别的道具。特别是在《Rogue》中，玩家最好在从中获得一些好处后再将其拾起。

种族灭绝

种族灭绝卷轴——总是被当成一种砍杀道具，最初出现在《Rogue》后来的某一版本中。当玩家阅读了这一卷轴后便能够摧毁游戏中某一类型的全部怪物。

但是在出色的roguelike游戏中，这种卷轴也具有权衡性。就像在《Rogue》中，当玩家使用了这种卷轴后，其它类型的怪物将变得更普遍，以此填补被消灭的种族所遗留下的缺口。并且在《Rogue》中，玩家只能使用一次这种卷轴，从而避免玩家摧毁更多怪物。

保护盔甲

这种卷轴将能阻止盔甲的优势被削弱，可以说这是游戏中非常有用的一种道具。这一卷轴是在在第五个版本的《Rougue》才出现在道具列表上，并且它也属于最稀有的道具之一。而之后的roguelike游戏之所以很少使用这一卷轴，主要有一大原因。

不管是敌人的攻击（基于各种版本的《Rogue》，可以是Rust Monster或者Aquators）还是陷阱都有可能毁坏盔甲。但是不可避免的事实是，在《Rogue》中，即使是永久的优势也会因为玩家糟糕的玩法或怀孕期而消失。例如当玩家不幸遇到响尾蛇时，之前所积攒的好运便会通通消失。平衡玩家获得超强盔甲（找到一套金属铠甲或使用迷惑盔甲卷轴）的方法便是使用Aquators去削弱盔甲，并在更深的地牢中更频繁地设置腐蚀陷阱。

玩家可以通过创建备用盔甲（因为玩家需要经过两轮才能进行转换，并且能够将其置于难以被删除的受诅咒的盔甲中，从而达到平衡），使用不会被腐蚀的皮制盔甲（因为这是游戏中最弱的道具，从而达到平衡），套上一圈保护盔甲（通过不断提高的食物消费而达到平衡），或使用保护盔甲卷轴等方法而抵制盔甲破坏者。

这么做并不存在弊端！除了只能影响一套盔甲外，但是说起来这甚至不能说是一种弊端。如果你在《Rogue》中的铠甲上使用这种方法，你就只能选择其中的一种决定。

《Nethack》让玩家在困惑时使用迷惑盔甲，从而提供一种抗锈且同样强大的盔甲。而《Shiren》则拥有电镀卷轴，不过某些怪物却能够摧毁这一卷轴的功效（这种情况却几乎未发生过）。但是在我看来，这两种情况均属于失败的设计。

游戏邦注：原文发表于2009年10月25日，所涉事件及数据以当时为准。（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）

COLUMN: @Play: Item Design, Part 1: Potions and Scrolls

October 25, 2009

By John Harris

It has been a little while…. This column is an in-depth examination of some of the most popular items within the two most-common categories: potions and scrolls, both of which we might term “one use” items for the fact that utilizing them consumes them.

Exploring a monster-filled dungeon is not what we might consider a healthy activity. If the game were just about looking around, mapping territory, and killing monsters until the player’s inevitable demise, the game might be interesting in an simplistic kind of way, but it wouldn’t have that roguelike spark. No, the player must get something out of the exploration. That something is treasure.

Treasure is the carrot held in front of the player’s face, leading him on into ever-more dangerous situations. The majority of treasure in most roguelikes is found laying around the dungeon. Some of the treasure is food, and the need to find more is what prevents the player from building levels indefinitely on the easier levels, but the good stuff is what pushes him downward. Unlike the trend in most RPGs these days, equipment is often a larger component of player power than experience level in roguelikes, and it is randomly generated.

The justification for treasure

Why is it so satisfying to find treasure? It cannot be denied that, without it, many roguelikes would be a lot less interesting. I suggest the reason that the expectation that players will find treasure, or other things and opportunities of value, in those dangerous places they explore is related to the exploration urge evolved out of humankind’s tribal pre-history. But I digress.

The randon treasure generation is the biggest scrambling factor in a roguelike. Monsters are random, but still appear in the same proportions on each level. Dungeons are random, but even with traps most of the time the maps are not themselves very interesting. But a single item of treasure, in a good roguelike, can have the power to change the game significantly, and the variety of powers they grant, intersecting with each other and the monsters and dungeons, is what allows different plays of a single roguelike to seem different from each other.

The biggest problem with giving players lots of treasure to find is in determining how powerful it should be. If it’s not powerful enough players may consider, why bother? If it’s too powerful then it’s unbalancing, and it is more the treasure that is the reason for success than the the player’s skill. It might be useful to examine the basis for treasure in the source from which RPGs arose: fantasy literature. Bilbo’s ring, for instance, enables him to overcome many of the dangers in the latter half of The Hobbit. Setting aside the ultimate identity of that ring revealed in The Lord of the Rings, a lot of the characters in that book kind of equate the ring’s powers with Bilbo himself. They say that there is something more to him than meets the eye. That thing is, literally, the ring. But he found the ring through his own wit and guile, so it does make a kind of sense to say that. And even with the ring, Bilbo is in danger and must use it wisely to escape from dungeons, dragons and wars. In other words, Bilbo’s possession of the ring is a manifestation of his ingenuity. So the treasure found in a roguelike, since it is gained by the player’s own wit and guile, is a manifestation of it, and it is the job of the designer, as creator and custodian of that world, to have it be fitting.

We’ve already given an overview of the primary types of roguelike treasure in a general article some time back. It is interesting that, although Rogue is over twenty years old now, the major item types provided by that game remain the major types used in nearly all roguelikes. This is the first of a number of columns that examines the primary types in detail. In this first column, we look at one-use items, which are used a single time and are then gone.

Disposable Magic: One-Use Items

The primary one-use item types, other than food (usually a simple case) are potions and scrolls. Some games also provide for random food items like berries and mushrooms. Shiren provides herbs, which are good for a small amount of food value when eaten, but generally function more like potions. This can be seen in the way that a good number of herbs provide special effects when thrown. ADOM has herbs which are unique in that their functions are not randomly scrambled, but are the same from game to game. (ADOM’s herbs have other unique and interesting properties however. They are one of my favorite things about that game, but they are a special case that doesn’t fit in with the general roguelike categories.)

Scrambled one-use items are among the more difficult to identify items in a standard roguelike. The biggest problem with identifying one-use items is that, once the item is gone, it isn’t there anymore. You only get once use with which to discover its purpose. And a few of these items are situationally useful, to the degree that the player may be helped considerably by using the item effectively, at the proper time or with specific preparation. And a few one-use items can cause a great deal of trouble; Rogue’s potion of blindness can be a game-ender if used at an inopportune moment.

Many games auto-ID potions and scrolls upon use, but Rogue and the Hacks do not. These games require that the item’s visible effect be detectable by the player, and are obviously the purpose of the item, before they’ll auto-identify. Some items have effects that are so obscure that they never auto-ID this way, forcing the player to either name it themselves from experience or expend an Identify scroll on it. Others only identify sometimes (like detection scrolls when there is something to detect), and some will prompt the player for a temporary name in some situations.

The one-use-only property of potions is one area where roguelikes differ from classic Dungeons & Dragons. By-the-book OD&D and 1st edition AD&D state that found magic items are unknown, but potions may be tasted and thus given a chance of identification without consuming the thing. In those games some potions have multiple uses, and others have functions that require the liquid not be drunk at all, but instead applied to an object or the skin, or in some cases the bottle merely unstoppered. The classic roguelike play style is directly inspired by these versions of D&D, and both Rogue and the Hack-like games provide for item uses beyond the basic “quaff.” In Rogue and Nethack throwing potions at monsters is an option for getting effective use even out of “bad” items. In Rogue, this may cause the item to affect the monster; in Nethack, a thrown potion breaks and may subject nearly creatures to a reduced “vapor effect.” Nethack also allows for dipping items into potions, and even mixing them together, each option of some strategic worth. Both games, also, contain Scrolls of Scare Monster, which are wasted when read. Their true value appears only while they’re resting on the floor. But even so, most potions are still meant to be drank.

There are usually many one-use items to discover in the game, and unlike random wearables (such as rings and amulets) the player usually will get a fairly substantial hint for what it does upon use, so, scrolls of identify are generally best used for other things. Significantly, identify scrolls themselves are random one-use items in most games. In many games, before any items can be identified by using them, the player must trial-and-error to discover them. Games that support selling items to shops often provide identification hints by offering items to shopkeepers, a tactic I refer to as “price ID.” The usefulness of this strategy ranges from slightly unbalanced in Nethack to nearly essential in Shiren’s Final Puzzle dungeon. Because this trick provides one of the few ways to narrow down object functions that doesn’t use the thing up or require knowledge of Identify scrolls, it is particularly useful when applied to one-use items.

What is the functional difference between the two classes?

Potions are much more likely to have an effect when thrown. The only roguelike (or roguelike series) I know that provides thrown item effects for scrolls is Shiren the Wanderer.

Potions are, basically, chemicals, and this avenues for useful non-magical potions are much greater than scrolls. For some games this is a significant difference: should a potion of magic detection locate a flask of oil? In Nethack, the most useful and potion is water. It is similarly useful in ADOM.

Potions may also be more versatile in their uses than scrolls. In addition to being thrown, it may be possible to dip items into them, or to mix then together. Nethack uses hard-coded potion mix results according to type. The Color Alchemy patch randomizes potion results, making them mix according to potion color and subtractive color mixing. ADOM puts a lot of work into its alchemy system, defining a number of mixture “recipes” randomly at the start of the game, and granting the player knowledge of them as he advances in the Alchemy skill.

While scrolls may have many varied effects, potions usually work on the subject’s physical form. Note, however, that this is not always the case; some detection effects may be implemented as scrolls, and others potions, in the same game. (D&D did this too sometimes; there is a line of potions for controlling various types of creatures. These potions work by the user drinking them; their influence then extends outward from the drinker, apparently.)

If the effect requires any further input from the player, particularly selecting an item to work on, the item will almost certainly be a scroll.

Here’s a list of some of the most notable items in the class, from various games, and their interesting properties.

Potions

… of Healing (and Extra/Full Healing, Cure Light/Moderate/Serious Wounds, and so on)

Other than weapons, potions of healing may be the most common item among all roguelike games. While most roguelike characters heal quickly (usually returning to maximum hit points after at most a hundred turns of rest), the danger presented from facing multiple opponents at once, or surviving an encounter with a single powerful monster, sometimes necessitates a way to restore hits rapidly.

One of the most interesting gameplay choices in these games is the traditional max-HP-boosting trick of healing potions. If you drink one when you’re at full health, many games will let the player push against the ceiling, giving him a tiny, permanent maximum HP increase. This seems like the better use of these potions at first, since the main method of gaining maximum hits in most games is gaining an experience level and those are rather harder to achieve, but the best move depends on your situation. Weaker healing potions are probably best quaffed for max health, especially later in the game, but the stronger ones can be so effective that they may come in handy when escaping from a superior foe, which the restrictive vision rules of Rogue make essential. Another obscure use of these potions is to instantly alleviate status effects like confusion and poisoning. Stronger types generally cure more types of these ailments. This use is of great importance in Nethack when facing certain rare, but very dangerous, Demogorgons situations.

One thing about healing potions is that giving the player an abundance of them can be less damaging to the design than you’d think. They require a turn to use, and a foe that really outclasses the player will probably put him right into trouble again with the next hit. Shiren the Wanderer has an item, the Chiropractic Jar, that instantly heals the player completely and restores most status ailments. These items have multiple charges and are not usually rare, and yet the game still has a reputation for lethality. This happens because the player must have both time to use the item, and the presence of mind to use it, and also because for their commonness they are still a limited resource, so the player tries to conserve uses. This often proves to be deadly.

… of Restore Ability

The only one of D&D’s six attributes to make it into Rogue is strength, which influences bonus damage done to monsters. The game begins players with a score of 16, and it also tracks “maximum strength,” which also starts at 16. There are monsters, traps and items in the game that can lower strength. All of these effects leave maximum strength alone. But unlike hit points, strength does not regenerate naturally over time. In Rogue, only the potion of restore ability, which resets strength to its maximum score, can undo damage done to it.

Like the danger of losing armor value, the danger of strength loss is mostly specific to a limited region of the dungeon, that which plays host to rattlesnakes, which by far cause most of its attribute damage. One consequence of Rogue’s sight rules (only one space around the player is visible in corridors and dark rooms) is that there are certain times when it is impossible to avoid taking a hit from a monster, which means sometimes strength loss is unavoidable. This makes restore ability potions fairly important.

When I say “maximum” strength, what I mean is the player’s current maximum capacity for it, which is considered to be its value when all attribute damage has been restored. Most other roguelikes provide more stats, with different functions, but they usually expand Rogue’s ability restoration potions to work on all of them.

… of Gain Strength (and other stats, and Ability)

In Rogue, a potion of gain strength increases the player’s strength score by one. If it was already equal to maximum, then both strength and maximum strength increase by a point. If the player has taken some strength damage though, then the result is that only one point is restored.

This means, if strength is later lowered, that drinking a restore ability potion will return strength to the new maximum. Having high strength is a subtle, yet significant, advantage, so it’s fairly important to save these for when the player is at max strength.

The trick to these two items lies in the inescapably of strength loss. Most characters will take at least a point of strength damage during the game, and often more. Both types of potions are generated randomly; it is possible that none of one type will appear in the game. If your strength starts getting dangerously low and you haven’t found a restore ability potion yet, is it a good idea to increase your damage done by one point by drinking a gain strength potion, or is it better to continue waiting, hoping to find a restorer to drink first? Keep in mind that the player doesn’t even know which potion is which at first, and often one potion type, poison, will drain strength. At their best, roguelike games are full of these kinds of choices.

ADOM has probably the best-developed statistic system of the major roguelikes. Whereas most games satisfy themselves with, or something like, D&D’s six stat system, ADOM has nine, and provides individual potions for improving all of them… and potions for temporarily boosting them, and potions solely for raising their maximum. (It also has the diabolical Potion of Exchange, that swaps them around. This can easily ruin your game if drank carelessly.) Additionally it has potions of Gain Attributes, which are more general but do not raise maximums. Of particularly awesome note: ADOM’s system has no hard limit on how high stats can rise, although it becomes much tougher to increase them as they go up. Interested readers are directed to the Stats chapter of the ADOM Guidebook.

… of Gain Level

Another example of a difficult choice is deciding just when to drink a potion of gain level.

As is normal for role-playing games, each experience level requires a rapidly-increasing number of experience points to earn in order to achieve it. Some games, following from old-school D&D, even use a doubling progression. Harder monsters are worth more experience points, it is true, but in many roguelikes they don’t quite keep pace with the higher point totals needed, meaning levels games come more and more slowly. Rogue, particularly, is infamous for monsters that generally get harder faster than the player gains ability. Rogue characters thus get put into ever increasing amounts of danger as they delve down, and every experience level counts.

As a consequence, the longer the player waits before drinking a potion of gain level, the more value he’ll get from it. If it’s used early, the experience points gained will be dwarfed by the amount received for killing even one monster. On the other hand, the longer you wait the less the portion of the game you’ll have made use of it, and if you get killed the advantage is lost.

… of Poison (and Sickness)

This is an example of a bad item, one that has no good primary purpose. Nearly all roguelike items have a good secondary purpose; bad potions can be thrown at enemies for example. Even the worst item can be useful if a nymph happens to steal it instead of something better. But the “usual” method of using potions, drinking them, will cause you grief if you try it with poison.

Take note, poison is not, in itself, fatal. That is a no-no in games where the player is expected to identify things through use. If the player must rely on using unknown things, then none of those things can be immediately deadly! This doesn’t mean using the item cannot be deadly if the player’s state is bad (low on strength when drinking a potion of poison), or if used in a non-standard way (zapping one’s self with a wand of death), or if a member of a very limited class of items (wearing Nethack’s amulet of strangulation, and even that can often be survived if the player prays.) Items also cannot make the game as good as lost. Rogue’s worst one-use item is the Potion of Blindness, a long-lasting potion that removes even the game’s slight one-space vision range, but it does wear off after a few hundred turns at most.

… of (something) Detection

While not obviously useful to new players, detection means are potentially one of the most useful objects in roguelikes. Monster detection allows you to choose your fights, item detection enables you to direct your exploration, and map detection points out useful escape routes. Note that detection items are in a gray area between potions and scrolls; different games allocate this power to these classes differently. Rogue has types of both! Food detection is a scroll, while magic and monster detection are potions.

… of Confusion, Blindness, Paralysis

These items are bad when drank, but sometimes good if thrown at monsters. Saying “bad” is relative to the situation; in Rogue, a potion of blindness can be useful when entering the Medusa floors.

They primarily exist as an identification foil, to add danger to identifying things by use and to make random potion drinking in moments of danger an inviable strategy. One-use items are fairly easy to identify

… of Thirst Quenching (and Water, Holy Water and Unholy Water)

Each of Rogue’s item classes has a do-nothing item, to throw off people who think all items must have some function. For scrolls it’s blank paper, and for potions it’s thirst quenching. The others are the wand of nothing and the ring of adornment. It is notable that Nethack still has all of these items, but with special uses for three of them.

Scrolls

… of Identify

The scroll of identify is, after healing, the most common of roguelike items. In many games they are also the most-often generated item.

Here is something I find very interesting. Scrolls of Identify are very common, but I am aware of no roguelike game that will purposely misidentify something. Nethack’s cursed scrolls of Identify identify fewer items, not lie to the player about what things are. D&D has dangerous objects that purposely resemble useful things, and the diabolical potion of delusion that, depending on a group’s play style, could cause the DM to lie to the player about what is happening to his character. Roguelike games, while tricky in the knowledge games they play, do not tend to go that far.

… of Enchant Weapon/Armor

These items are the scroll versions of the potion of Gain Strength. That potion increases the player’s damage-dealing abillity by increasing his physical attack bonus. The scrolls increase weapon attack bonus and decrease enemy hitting chances, while the player is using a specific piece of equipment.

All of these items improve the player’s state indefinitely. They do not expire naturally, but must be undone by enemy attack, unfortunate item use, or trap. That makes these items extremely useful. Although a single point of bonus is a rather subtle effect in a single encounter, over time the benefits are profound. If the player is lucky enough to find several of these the game will become much easier, maybe even too easy. Most games guard against this possibility by limiting how high strength can be raised, or how far an item can be enchanted. It is kind of a cheap way around the problem, since it means a whole class of item suddenly becomes useless just because the game designer thinks the player is getting too powerful, but it is frequently used.

A particular note… in Rogue, scrolls of Enchant Weapon are unusual in that they increase one of a weapons two pluses. That game distinguishes between pluses to-hit and to-damage, and the scroll decides randomly which of the two values is increased. Some Rogue variants split Enchant Weapon into two separate items. And some go the other way, and combine the Weapon and Armor scrolls into a single “Enchantment” scroll, which asks the player which item will be subject to the item’s power upon reading.

In most roguelikes, these scrolls function immediately on a relevant item in use at the time. If no weapon or armor is in use, the scroll’s effect is wasted. Nethack uses this as the basis of a subtle trap; one of its bad scrolls is that of Destroy Armor. If you’re reading unknown scrolls, you might want to wear armor in order to take advantage of an unknown Enchant Armor scroll. But what if that scroll should be Destroy Armor instead? Another possible trap, used by other games, is the scroll that asks you for an item to operate on, but that doesn’t tell you what for.

As an extra ability, these scrolls also lift curses from the item they operate on.

… of Vorpalize Weapon

What does it mean, to “vorpalize” something? No matter what one might have gleaned from its use in video gaming, vorpal is actually a nonsense word. It can be traced back to Lewis Carroll’s Jabberwocky, where it is applied to a sword and can be assumed by context to mean powerful. Role-playing games have adopted it. although there is no consensus about what it should mean.

Rogue contains a scroll called Vorpalize Weapon. When read, it makes the player’s weapon flash violently for a moment. It applies a pretty good enchantment to the weapon, and additionally chooses one of the monsters in the game to be the weapon’s target foe. The next monster the player attacks of that type will die instantly. There is a drawback however. If the player tries to use a second Vorpalize Weapon scroll on the same weapon, it is destroyed!

The ideas here is to punish the player for being too greedy. Of course, the player doesn’t know how greedy is too greedy until he loses his weapon. In practice, this becomes another of those little things players must learn as they play, another fact that must be acquired in order to eventually win. If this seems rather a harsh way of teaching the lesson… well, Rogue really isn’t that long a game.

Nethack will destroy a weapon or a piece of armor if it is over-enchanted. When a weapon is enchanted beyond its safe limit, it vibrates warningly. A further enchantment has a very high (but not for certain) chance of destroying the weapon.

… of Confuse Monster

To a new player, this is one of the more enigmatic items in Rogue. Upon reading the only immediate effect is that the player’s hands begin to glow red. This causes the next monster the player strikes to become confused for a short while. That is all. In principle this is a powerful item, although reading it in advance of combat usually creates a risk of it being wasted on a weak monster.

… of Scare Monster

One of the most mysterious items in the game if the player doesn’t know its secret. It is also the only one that can be identified without picking it up. In fact, especially in Rogue, it is best not to pick it up until you’ve gotten at least some use out of it.

… of Genocide

The scroll of Genocide, often thought of as a Hack item, got its start in one of the later versions of Rogue. When read, it wipes out one entire type of monster from the game.

Items that powerful, in a good roguelike, will have a tradeoff, and in Rogue it is that other types of monsters become more common, to fill the generation hole left by the eliminated species. Plus, according to the Rogue Vede-Mecum at least, there is only one of these generated in a game, preventing the player from wiping out too many monsters.

… of Maintain Armor

This scroll, which prevents armor pluses from being reduced, is one of the most useful items in the game. Seriously, it is almost overpowered! It is a late addition to Rogue’s item list, appearing in V5, and it is one of the rarest items. There is a good reason that many later roguelikes do not include it.

Armor can be harmed both from enemy attack (by Rust Monsters or Aquators, depending on the version of Rogue) and from traps. One of the many little devious facts about Rogue is that even permanent advantages can usually be undone due to unwise play, or even bad luck. Getting your strength up can be undone from a single unlucky encounter with a Rattlesnake, for example. The balance between the possibility of the player getting super strong armor, from finding a suit of plate mail and a number of Enchant Armor scrolls, is that Aquators will easily weaken armor, and rust traps become progressively more common in the deeper dungeon.

These armor ruiners can be overcome by working on building an emergency set of armor (which is balanced due to the fact that it costs two turns to switch to it, and the possibility of putting in cursed armor which cannot be removed easily), by using unrustable leather armor (balanced by its being the weakest in the game), putting on a ring of Maintain Armor (balanced by increased food consumption), and reading a scroll of Maintain Armor, which… has no drawbacks.

It has no drawbacks! Except perhaps due to it only affecting a single suit, which is nowhere near as bad a drawback as the other things. If you put this on plate mail, you have just made one of the few unequivicably good decisions you can make in Rogue.

Nethack’s analogue for this is reading a scroll of Enchant Armor while confused, which provides rustproofing, and is similarly powerful (although possible to remove in rare cases). Shiren has Plating scrolls, the effect of which can be removed by a certain monster (which nearly never happens). Both are, in my opinion, subtle failures of design.(source:gamesetwatch)