作者：Harold Myles

《XCOM》所具有的一大特征（也是最初的《X-COM》所具有的特征）便是游戏呈现出了两种不同的游戏层面：策略层面和战术层面。尽管游戏类型是相互独立的，但是这两个层面却缠绕着各种不同的机制和子系统。所以一个层面的性能表现将深深影响着其它层面。除此之外，游戏的胜利和失败条件将只能主导着其中一个层面。

xcom(from psnation)

也就是策略层面只能呈现出游戏的失败条件，而战术层面则只提供了游戏的胜利条件。玩家为了赢得游戏或避免输掉游戏所做出的选择都不是那般简单。而《XCOM》正是利用了一些非常简单且透明的机制让这些选择变得更加复杂且透明。

改写自Keith Burgun的一句话，即如果一个选择不再模糊，它便不再是选择。

从策略层面上来看，游戏呈献给玩家一个“外星人绑架”事件。

这一事件能够让玩家在避免输掉游戏与赢得游戏之间做出选择。玩家的选择对于最终目标的影响也非常明确。而令人印象深刻的是，这些选择并未因此变得简单或清晰。

“外星人绑架”事件通过使用一种简单的方法提供给游戏最直接的机制，从而将这两个层面有效地整合在一起：

三个选择

每个选择都将提供一个好处帮助玩家免于输掉游戏（管理恐慌）

每个选择都将提供一个好处帮助玩家赢得游戏（发展技术，装备和军队）

可以分别权衡每种好处

但最终只能做出一个选择

选择的难题在于将两个不同的目标带进一个单一的选择中。根据当前的游戏状态以及一些随机混合元素，赢得游戏以及避免输掉游戏的最佳选择并不相同。实际上，赢得游戏的最佳选择对于不输掉游戏来说可能是最糟糕的选择，反之亦然。

我将详细描写上述的机制，因为我认为它们是游戏中最有趣的设计元素之一。并且它们能够带给玩家更多的紧张感。所以我将在之后的内容中详细阐述这一系统是如何作用于那些我们并不是很熟悉的元素。并解释为何“外星人绑架”事件中的两种奖励倾向于作用两种不同的游戏目标。

输掉游戏：

输掉游戏的条件便是管理Doom Tracker。当每个国家到达一个高度恐慌程度时，这个国家将被永远驱逐出游戏，而Doom Tracker数量将继续增加。最终当Doom Tracker达到8个时，游戏也将永远结束了。

国家的恐慌程度是取决于策略层面上的成功完成事件，就如“外星人绑架”事件。在这些事件中做出选择将能够帮助玩家提高或降低不同城市中的恐慌程度，这也是玩家控制Doom Tracker的主要机制。如果能够进行有效的掌控，玩家便不会输掉游戏。

同时我们还需要注意的是这一系统并不会提供任何获胜条件。玩家只能通过控制Doom Tracker去避免输掉游戏，但是却找不到任何直接的机制能够帮助自己获得胜利。

赢得胜利：

相对于策略层面，战术层面将只会提供获胜条件：完成游戏最终的战术任务。

实际上当我在写这篇文章时，因为出现了某个漏洞而导致玩家即使输掉了所有队员也仍然能够重新挑战最后的任务（游戏邦注：甚至是在Ironman模式中）。在战术层面上玩家并不会直接输掉游戏。

“外星人绑架”事件提供给玩家管理恐慌的方法，除此之外它还呈现了一些可行的奖励：科学家，工程师，金钱或更高技能的军队。每种奖励都能够推动玩家不断提高自己的能力，并增强自己在战术层面上的成功几率。

混合了这些可行的奖励，即推动胜利条件和管理恐慌，并避免失败条件，“外星人绑架事件”既保留了容易理解的游戏机制，同时也呈献给玩家一种深深的紧张感。

（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）

XCOM: Clear Choices, Tough Decisions

by Harold Myles

By mixing both tangible rewards, that progress the win condition, and panic management, that postpones the loss condition, XCOM’s Alien Abductions events deliver a lot of tension while remaining an easy to understand mechanic.

One of the key features of XCOM, as well as the original X-COM, is that the game presents two different gameplay layers: the strategy layer and tactical layer.  These layers, while separate and discrete in gameplay style, are intertwined by various mechanics and sub-systems. Good or bad performance in one layer will likewise affect the other layer.  Additionally the games winning and losing conditions are each exclusively the domain of only one of either layers.

The strategy layer presents the game’s only losing condition, while the tactical layer provides the game’s only winning condition.  The choice between winning the game and not losing the game isn’t always simple.   XCOM employs a surprisingly simple and transparent mechanic for making those choices even more difficult and ambiguous, and that is a good thing.

Paraphrasing Keith Burgun; a choice isn’t a choice unless its effect is ambiguous.

Periodically, on the strategy layer, the game presents the player with an Alien Abduction event.

These events provide the player the opportunity to choose between not losing the game and winning the game.  How the player’s choice will affect either goal is clear and transparent. Impressively, that doesn’t make the choice any easier or less ambiguous.

The Alien Abduction events provide the game’s most direct mechanic for mixing these two layers together.  And it does so in a simple way:

Three choices

Each choice provides one benefit for not losing (managing panic)

Each choice provides one benefit for winning (progressing technology, gear and troops)

Each benefit can be clearly gauged seperately

Yet only one choice can be made

The conundrum of choice is achieved by blending the two different goals into a single choice.  Depending on the current game state, and some random mixing, the best choice for winning the game and the best choice for not losing the game may not be the same. In fact the best choice for winning may be the worst choice for not losing, and vice versa.

That is pretty much the end of this article.  I just wanted to describe the above mechanic because I thought it was one of the more interesting designs in the game.  Primarily because it is so simple yet achieves so much tension.  The rest of this article describes some more detail in how this system works for those that may not be familiar. And may make it more clear why the two rewards presented in the Alien Abduction events tend to favor two different game goals discretely.

Losing:

The condition for losing the game is stated upfront in a clear way: the Doom Tracker.  For each country that reaches an elevated panic level, that country is permanently removed from the game, and the Doom Tracker is permanently incremented by one. When the Doom Tracker reaches eight then the game is over.

A countries panic level is managed by successfully completing events presented on the strategy layer, such as the Alien Abduction events.  Choosing between these events the player can raise or lower the panic levels of the various countries, which is the player’s primary mechanism for managing the Doom Tracker.  And ultimately not losing the game.

The important thing to note is that this system does not provide a win condition.  The player can manage the Doom Tracker only to keep from losing, but it provides no direct mechanism for the player to win.

Winning:

Mirroring the strategy layer, the tactical layer provides the game’s only win condition: by completing the game’s last tactical mission.

In fact, at the time of this writing, due to a supposed bug, the last mission can be repeated when the player’s squad is wiped out, even in Ironman Mode.  There is no way to directly lose the game through the tactical layer.

Alien Abduction missions provide a method for managing panic, and additionally provide a more tangible reward: scientist, engineers, money, or highly skilled troops.  Each of these rewards allow the player to progress his capabilities, and enhance his chances of success in the tactical layer.

By mixing both tangible rewards, that progress the win condition, and panic management, that postpones the loss condition, Alien Abductions deliver a lot of tension while remaining an easy to understand mechanic.（source：GAMASUTRA）