The following piece spoils elements of Fallout: New Vegas – Dead Money and much of Outer Wilds – Echoes of the Eye.
I highly recommend playing both for yourself before reading this analysis.

A video game conditions players to rely on certain tools to get through the game. These tools, more often than not, are empowering. In Fallout: New Vegas, the crutch of a large inventory system with countless guns and countless bullets and other necessary supplies eventually makes the player into an unstoppable killing machine. Outer Wilds is a game about the freedom of exploration and the joys of unrestricted movement. New Vegas, to a lesser extent, is also a game about exploration and solving mysteries and quests. So what happens when you take away both games’ freedom, and pull everything into a tightly compressed experience? Well, you get horror.

It’s a divisive way to create horror, but one of the most effective methods in video games. It is very simple – when a player has come to expect leniency, or to be able to survive through the use of a certain mechanic, take it away from them. Add a dense atmosphere of eerie audio and creepy visuals, and you have made some great progress towards making a video game truly frightening.

The key mechanic in Echoes of the Eye centers around torches, which you use to tap into a dream-world of sorts. Inside the dream-world, you may bump into the other inhabitants of the world, these large, owl/elk creatures, the alien creators of the large worldship you find yourself on. They are, as it turns out, not friendly, and are more than happy to forcefully eject you from the dream-world. The situation is made scary by a few different factors. You’ll first note the oppressive atmosphere that I discussed here, and the incredible darkness. But some of the areas of the dream world are lit up. They can be, as it turns out, extinguished. But in extinguishing the lights, you release the alien guards, who will stalk the place. The releasing of the enemies is a voluntary act, and in doing so, creates a greater sense of tension in this instance. You are aware you are stepping into danger, and you are doing so voluntarily. The screech of the owls in the distance merely heightens the expectations of what is to come.

Since they can see in complete darkness, you have to use the lantern. But when you use the lantern, they can obviously see you clear as day. So you have to use it in short, controlled bursts, as the looming predators will charge if they see you shining your light for more than a couple of seconds. By holding down the relevant button, you can “focus” your lantern’s light onto a single point, but this makes you move a lot slower. It is a trade-off that makes you both more aware and more vulnerable. And vulnerability is the key to the feeling of fear in video games. Safety and complacency make a player bolder and more likely to approach a scary place or character without as much tension or apprehension. The light in EotE is truly pathetic. It barely reaches a few steps in front of you, so you have to pop headphones on and listen closely to the sound of the footsteps. This heightens immersion, which is good, as well as makes the player more vulnerable to the horror by forcing them to get up closer to the sounds. Dead Money is much the same. You have to turn your sound up or pop some headphones on to hear the beeping of the radios that will blow your head up if you’re not careful. You become closer to the experience and thus more vulnerable to the rest of the atmosphere, becoming more immersed and hopefully, more frightened.

This is all great horror set-up, but Outer Wilds pulls three further tricks that make the game’s horror even more elevated. There’s a trick you discover most of the way into the DLC where if you leave your lantern some distance away, and step out of its range, you enter into the real view of the dream-world. This real view lights the place up, and lets you see and identify the guards stalking the area much more easily. But the puzzles in the dream-world are all centered around the presence of the lantern. So even if you discover this trick, it will only help you through certain, shorter sections – then you will have to backtrack and grab the lantern again. If you also wanted to abandon your lantern, you have to leave it in the pitch darkness (remember you’ve likely extinguished all the other lights at this point) and walk blindly into the dark to see the lighter face of the dream-world. It was a little game design point I found particularly effective. Even when the player thinks they’ve found a way to circumvent the horror, they realize that the horror cannot be circumvented, that their fears must be faced, and that’s really quite brilliant.

The second of these last tricks is to let the player walk through the dream-world without spawning in any of the enemies yet in two of the areas. Remember, you have to spawn them in yourself. In a couple of spots, you can hear the clomp-clomp-clomp of an enemy’s footsteps, but cannot see them. Tension raised successfully. So you can explore these areas, soaking in their oppressive and already-dark atmosphere, but can never find any of the enemies. There’s one powerful area where you can peer through a window and see a silhouette against a moving projector screen. At that stage, I hadn’t yet seen any of the enemies, so this was my first, haunting glimpse of a real, moving one. It’s a shame that this is one of the few bits that can be ruined by the game’s nonlinearity, since you might have already seen them elsewhere, but it’s still a great horror moment, as well as an emotionally moving one, as the alien is looking longingly at pictures of their homeworld that they can never return to.

The final little trick is making the lantern the only tool you can use. There is no jetpack for vertical or quick movement. All you can do is either focus the lantern, or hide its light, both of which are genuinely tense experiences. I like to think it’s not often that a game manages to frighten me, but there was a moment in the darkness where I looked ahead, flicked my lantern on, and there was an owl looking straight at me. I jumped. It was a moment that wouldn’t have worked without all the previous set-up – the ambient noise, the stripping away of helpful tools and familiar mechanics, the overwhelming darkness, the setting up of the tension – everything just works beautifully. New Vegas’ Dead Money gives the players so little to use that every single item becomes precious, even bad weapons and single bullets. Missing shots is something of actual consequence, raising tension and requiring players to spend longer scrounging for bits and bobs in the environment – further increasing the atmosphere!

I’m sure you can see how and why horror of this style works in video games. Through the construction of areas that require new approaches, as well as making the player less capable and less powerful, more powerful enemies that would have been merely a fun obstacle before are now frightening adversaries whom you’d rather sneak by than engage. The magic of horror is that even when you understand how and why it works, surprising moments like the owl staring right back at me as I flick my light on still manage to frighten because the game has taken the effort to set up all the necessary immersive elements before it tries its hand at frightening me. Dead Money opens with a dilapidated courtyard blaring out a radio from centuries ago. It is that sound that echoes through the rest of the DLC, creating a truly oppressive atmosphere that drains your energy and torments the player as they struggle for survival. The fear of being surrounded by Ghost People, alone, when you are out of ammo – that would never occur in the base game. The horror elements present in both expansions is simply genius, and I look forward to replaying both of them again and again further in the years to come.