此层级，正如大多数人所看到的那样。
生存难度：生存難度：
等级等級 unknown
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Level 421是一个高度统一化的环境，在人们可以想象到的任何地方都只有一种物质。然而，大多数人从未见到过组成此层级的物质，而仅仅能感受到那些物质紧紧包裹着他们。一种大小近乎无限的重量正在其之身体周围回旋，造成一种轻微的瘙痒感，使得他们的肺部收缩并变得沉重。而只有当人们对此层级感到恐惧时，这些物质的影响才会出现；而当现实刺痛他们时，更加如此。而当恐惧袭来，人们的身体动作扰乱了整个高度统一的环境时，这个层级就将夺去他们的生命，将他们变为在此处丧命的成千上万人之中的一个一。
Level 421 is a uniform environment, occupied by one sole material in all conceivable directions an individual can face. Most never see the material the level is made of, yet constantly feel it encapsulating tightly around them. The weight of an infinite mass gyrating around their body in a light, almost ticklish sensation that constricts and weighs on their lungs. The effects of the material only become noticeable after the dread of the level has already set in; adding to the panic one feels when reality hits. When the panic sets in—and the movements of one's body disrupt the uniform environment—the level has already claimed them, and their life becomes another statistic to add to the thousands it has already tallied.
只有凭靠运气才能看到的层级之图像。
描述
Level 421是一片无穷无尽的球坑，在长度、宽度、深度、高度上皆为无限延伸的。层级之中的所有流浪者——当然，严格来说，并不能将“流浪者”用在这个层级内——只处于无限的塑料球的中心。然而，Level 421的中心就如同它的边界一样，只是无稽之谈。层级内的两位幸存者之间的距离就如同层级本身一样是无穷无尽的，而这距离无论如何都不会缩短。
无边无涯，就算Level 421内存在着外部的光，其也无法渗入幸存者们可触及的任何地方。那些有幸带着手电筒、打火机、灯笼或更多异常光源的人不仅将是唯一可以在层级内看清的人，也将是唯一足够幸运到可以在层级内幸存的人。尽管此层级的环境在理论上是高度一致化的，所有光源——无论大小如何——都提供给了那些在你身边埋藏着并蠕动着的东西一部分环境；提供给了你一种对于缺乏安全感的环境的了解。最重要的是，提供了生存的关键。
空气只存在于聚合物球体之间的缝隙，以及球体之内。它的成分类似于可呼吸的大气——尽管它明显含有高浓度的二氧化碳和低浓度的氧气。虽然这样的失衡并不足以引起中毒，但增加的二氧化碳将会引起吸入者轻微的神志不清。然而，这种影响可以通过缓慢呼吸，保持稳定，并在穿越层级时持续冷静来抵消。
层级内的塑料球尽管处在一片无边无际的环境中，但仍然紧紧相挤在一起。稠密且拥挤的环境允许其中的人们缓慢地游泳，运用力来改变他们周身球体的排列组合，以缓慢而稳定地前进，踏上毫无结果的旅途。
探索层级。
流浪者穿越Level 421时，需要缓慢地推动，而在这片如此简单的景象中这么做需要的力度在常人看来不可想象。而在穿梭时，对这片景象的认知和感觉就将开始逐渐形成。
幸存者身边充满着毫无改变且毫无意义的色彩，幸存者可以感觉得到它正在循环——更坏的设想是，它根本没有在移动。对于幸存者来说，缓慢的游泳通常会让他们感到不舒服；就好像如果游得更快的话，就可以看到别的一些东西了。
幸存者经常对周围的海洋施以更大的力，试图更快地前进，他们用自己的手臂、双腿、手、脚甚至于用脸更快地推动，全力试图走得更远一些。而更快的推动加快了他们身边塑料球的移动，弹力塑料发出的空洞声音充满着他们的耳朵。
在加速无果的情况下，幸存者们经常要么陷入恐惧，要么试图用比之前还要快的速度游泳。而无论幸存者如何选择，陷入恐惧或再度加速都会导致自己周身的物质更快地下沉，直至打破幸存者身下球体和他们自己之间的完美平衡。
如果那平衡被打破，他们就将开始下坠，坠入那无限的深渊。抓不住任何东西，拿不住任何东西，当然，周围的物质仍没有任何变化。下坠的人永远在下坠。迷失在无法触及的深处，坠入层级的魔爪。
在层级内受困。
或者说，理智者或知识渊博者在尝试游泳穿过Level 421时可能会选择保持慢速。这些人可能会让他们的头部始终端平，动作始终缓慢，以使他们的能量完美地保存，以便正确地穿过Level 421，而非是坠入深渊永不复返。
Alternatively, the sane or the knowledgeable may choose to keep slow whilst attempting to swim across Level 421. These survivors may keep their head level, their movements sparse, and their energy perfectly conserved in order to properly navigate Level 421 without dooming themselves to fall for eternity.
虽然对这样做的幸存者来说，环境似乎仍然是毫无改变，但那些仍然保持着正确的运动姿态的人却可以始终安然无恙。而当这些幸存者开始吸入周围稀薄的空气时，呼吸就有可能逐渐变得困难。
Though the environment feels as though it unchanges for these survivors, the ones that follow the correct movements religiously stay afloat. Breathing may begin to get tough for these survivors as they begin to inhale all the sparse air around them.
当这些人缓慢移动时，他们身边的塑料球将在他们身边逐渐分散开来，始终如一的冰冷塑料聚合物的感觉轻轻拂过人们的皮肤和衣物。然而，一种更为坚实的物质会开始摩擦人们的下肢；一种更长的、更温顺的、有着纤毛的物质，但其仍然和此层级的其它物质一样冰冷。而当它引起幸存者的注意的时候，这种感觉就已经消失了，取而代之的是再次开始的旅行。
As they slowly move, the plastic balls around them continue to disperse around their bodies. The same, continuous feeling of lukewarm polymers brushing lightly on one's skin and clothes. Eventually, however, something more substantial begins to graze one's lower limb. A longer, smoother, ciliated material, yet still one just as lukewarm as the rest of the level. By the time survivors even begin to notice though, the sensation is already over, and their travels resume.
如果流浪者继续向前，类似的感觉就仍可能会出现。人们可能会把它当作是
Whilst the survivors press on for longer, similar sensations occasionally transpire. Individuals may pass them off as tactile hallucinations, or anomalous materials buried amongst all else. However, as the brushing-past gets more frequent, as do the sounds of more plastic balls subsiding.
Some survivors pause, only to hear the sound of movements persist. Regardless of reaction, many attempt to move once more. Whilst both arms try to persist, only one leg moves. The feeling of a cold, smooth material clasped around one's lower leg.
Unable to progress, the only sounds that follow are the sounds of more plastic polymer displacement from sources not from oneself. The sounds grow in volume, proximity, and in numbers, all whilst more cold skin envelops and cocoons you in place ever more. With every new organ that holds yet another section of one's body, one noise of shuffling ceases; only to then be replaced by two new ones.
Eventually, after one's whole body is constricted and restrained, the sounds of moving plastic spheres are replaced by a growing sound of static. The sound approaches slowly, only becoming obvious when it is the only noise one can perceive. As it grows closer, the hands grip tighter, sinking oneself deeper into the plastic Mariana's Trench.
Perhaps it is possible to wriggle free, to instead suffer the eternal fate of plummeting rather than the eternal fate of death. Ankles and fingers still slightly wriggle, the neck still tilts and turns, and the rapid, panicked breath indicates there's still enough room for movement. As the static grows, distorting and growling, you feel small parts of you becoming free.
First an ankle, then a palm, followed by three fingers on the opposing hand.
The grip of the ciliated flesh around oneself weakens as more of you gets free, able to shuffle with more force and vigour that eventually frees entire limbs.
As more of you is freed, the sounds of displacing plastic balls begin to reignite. Initially, one may believe the sound is of the ciliated flesh beginning to vanish.
But as the sounds multiply, as does the quantity of flesh that latches onto yours.
It becomes harder, yet not impossible, to escape. Only a wrist getting free. It feels enough to escape, use a free hand to pry off whatever one can…
. . .
但是已经太晚了。
. . .
入口与出口
- This level is mainly accessed through ball pits scattered around Level 0, Level 3, and Level 853, as well as within designated play areas inside Level 283 and Level 458.
- Sinking into these ball pits will feel tough and difficult, though it is equally unpreventable as soon as the immersing commences.
- Select survivors reportedly hear the sound of static upon beginning to sink in, however, such reports remain unconfirmed.
- Sinking into these ball pits will feel tough and difficult, though it is equally unpreventable as soon as the immersing commences.
- Some speak of exits to Level 729, accessible only by noclipping through patches of plastic balls that are one uniform colour. Whilst such areas do exist in the level, doing such a thing would be almost impossible to do seamlessly.
- Such an exit would also require one to have constant access to a light source, as blind-guessing where such a passage out would be without a source of illumination would be pointless and fruitless.