In the originalLeft 4 Dead's
“game_sounds_weapons. txt”
file, listings for a flare gun and a LAW rocket launcher can be found. They are all commented out. It is likely that these weapons were scrapped early in development, as none of the pre-release footage shows either of these weapons. Also there one can find mentions of some upgrades such as a knife and a blinding flash.
In Left 4 Dead 2there were originally going to be a riot shield and a didgeridoo as usable melee weapons in the game. However, they were cut. The riot shield was fully modeled and textured and can still be spawned in-game both via the console and during custom campaigns, while the didgeridoo had a low-poly model, but no textures.
大致是说在这个武器音效文件里，可以找到信号枪以及LAW火箭发射器的踪迹。以及防爆盾跟迪吉里杜管这俩被cut的武器（防爆盾可以用mod或插件刷出，另一个就……）

催更

不要咕咕啊

求生之路胎死腹中的设定之一：技能系统
Also hidden in the files are skills but unlike the upgrades there is no way to activate them and if you try to you will lose control of the character your playing as. Some of the skill names make references to classes in Team Fortress 2.
大致是说，在游戏的文件中隐藏了技能系统这一设定。但与升级不同的是，没有办法激活它们，如果你试图激活它们，你将失去对你所扮演的角色的控制。一些技能的名称引自军团要塞2。
这是技能系统的一些残留数据，看起来更像是职业兵种。
55. aPackrat
56. aCommando
57. aOpenfire
58. aDefender_0
59. aGuide
60. aKnuckles
61. aEngineer
62. aSprinter
63. aGroupie
64. aClimber
65. aSoldier
66. aDemolitions

仔细观察这张图片的亮点

这个是求生之路2测试阶段，燃烧弹药升级。
这里的燃烧弹药包是跟急救包一样的形状，并且捡起来就是使用的状态。

有人知道这个么

这个就不用说了。早期一些插件服的盾牌，打出时会有高尔夫杆的残影。

还有这个

测试阶段的求生之路2大厅界面

这个是求生之路2燃烧弹药升级的另一个版本

这里的持枪方式都是用求1的，备弹也与求1的一致。
这里的SCAR是全自动的

更

关于NICK：
In the commentary for Left 4 Dead 2, the developers state that Nick's character was originally an escaped prisoner that stole a nice suit, but he was eventually adapted into his current con-man persona. It is probable that he is still a convicted felon, as Nick can make a remark to the effect that he's not legally allowed to own firearms ― a constitutional right Americans only lose if convicted of a felony or some misdemeanors involving a weapon.
在《Left 4 Dead 2》的评论中，开发者称尼克的角色设定最初是一个偷了一套漂亮衣服的逃犯，但他最终被改编成了他现在的骗子角色。很可能他仍然是一名重罪犯，因为尼克可以说他在法律上不被允许拥有枪支——这是一项宪法权利，美国人只有在被判重罪或涉及武器的轻罪时才会失去这项权利。

Also supporting this is when approaching the wedding area onThe Riverbank, he may state "This brings back some bad memories," or that "it's not easy to get blood out of a wedding dress", which hints at some violent incident on his wedding day.
在“河岸”这一章节中，他可能会说“这会让人想起一些不好的回忆”，或者说“从婚纱上流血并不容易”，这暗示着他在婚礼当天发生了一些暴力事件。