Outer Wilds was an expansive, planet-trotting puzzle adventure, but its first and only expansion, Echoes of the Eye, is a more condensed and focused encapsulation of all the elements that made it great. Instead of taking place throughout a solar system, Echoes of the Eye hones in on a singular location, which itself is broken up into distinct areas of interest that keep the intrigue and sense of discovery alive and well. But it's also not without some new stumbles that introduce infrequent but inescapable frustration to the game's core time loop.
Echoes of the Eye doesn't require any prior knowledge of the format of Outer Wilds to start or complete, but it's certainly tuned for players who have accustomed themselves to the type of thinking its puzzles require. Even starting the expansion is a delightful puzzle, giving you a thin breadcrumb trail to follow that exposes a secret so deviously hidden that it's easy to believe it was always there to begin with. This expansion is meant to sit parallel to the challenges of the main game, which means you won't have to be familiar with its mechanics regarding quantum physics or superposition. At the same time, not having played the original adventure will make Echoes of the Eye more challenging, given how it depends on a way of thinking that is only gained through cutting your teeth on the puzzles of the main game.
The expansion takes place on The Stranger-- mysterious ship that has supposedly always been orbiting the solar system in plain sight. It's a craft from another universe entirely, drawn to your home by the same intrigue surrounding the Eye of the Universe, which drives all the stories throughout Outer Wilds. The Stranger is its own small ecosystem that wraps around itself and subscribes to the same time-based changes that all the other planets in Outer Wilds follow. As soon as you start, you're on the same 22-minute timer as before, with crucial changes within The Stranger requiring you to become familiar with how they affect the entire area over time.
This is a loop that's easy to become comfortable with, as each small excursion to the Stranger lets you slowly peel away at the many layers it has to offer. The adventure is kept fresh by a shakeup in how you gather information, too. In the past your handy translator made you privy to ancient conversations that would inform your next steps. Here, instead, your translator is completely useless, with many of your initial discoveries coming from scattered projector slides that you'll need to illuminate to decipher properly. Not having direct descriptions leaves some vagueness on the outskirts of each hint that makes the solution slightly more taxing to arrive at, but even more rewarding to figure out too. The gentle nudges towards specific mechanics are even more refined in Echoes of the Eye, giving you enough to work with but being delicately restrained to make you feel like a genius once you arrive at the solution.
It's impressive how much Mobius Digital has squeezed out of a single area, too, removing the stress of having to travel from one planet to another within sometimes tight time constraints, but also not removing that sense of urgency from the challenge. The Stranger has its own routine that you'll need to study in order to reach fresher information, with many of its idiosyncrasies only revealing themselves well into your adventure. The depth that this one area offers dwarfs that of many of the larger planets that it orbits, giving you more reason to study smaller details in order to unravel the full mystery of the craft. There are so many new mechanics and challenging new puzzles to solve that this expansion that it could have been its own sequel.
The mystery of The Stranger is one that doesn't recontextualize the core narrative of Outer Wilds, but instead just tactfully adds a new layer to it. There are no revelations that take away from the journey you might have already had with the original but adds to it in a way that makes a second viewing of the original ending as rewarding as the first. Its story follows a new species that has discovered this solar system and its connection to the Eye of the Universe, detailing their interest with the phenomenon and the sacrifices made in order to track it down. Much like the original, you're exploring the aftermath of a civilization that has long left this world, piecing together what they were attempting to discover while also empathizing with their ultimate failure.
Unlike the original, though, horror makes up a big part of the overall tone to this adventure. There's a more sinister undertone to the sacrifices that this new civilization made in order to complete their journey, and a deeply unsettling revelation as to what ultimately transpired at the end. This comes through early in the expansion, with haunting musical tone shifts accompanying burnt out frames in many of the slides you'll find, as well as the unsettling silhouettes of some of the figures contained within them.
This mood is amplified later in the expansion, where danger-free exploration takes a turn into frustrating stealth sequences. Although you're still attempting to figure out new puzzles in these sections, many of them are overrun by enemies that will reset your progress entirely should they catch you. Making matters more complicated is the lack of light in most of these areas, with your only reliable source being the lantern in your hand that also immediately gives away your position. So not only is knowing where enemies are important, but being able to navigate blindly in the pitch darkness is often required too.
This is the only portion of Outer Wilds where your progress is stifled by your ability to sneak around in the dark and not simply by your own understanding of its world, which is a jarring change in the context of everything the game has required of you up until that point. There are some ways to shorten these sequences with clever setup, but they can be entirely undone by just one false move in the dark, so that the effort feels undermined by the consequence of a failure that feels like it can come easily, and since each new loop requires you to work your way back up to that point this can be aggravating. It's the only time, across the main game and this expansion, that Outer Wilds' loop feels frustrating, and it's consistently disappointing to brush up against.
It's a pity that it concludes so much good that comes before it. The flowing ravines of The Stranger make for a pleasant change from the frequent space flight of the original game, and it's made even better by the accompanying soundtrack from returning composer Andrew Prahlow. The ebb and flow of confusion and revelation is as satisfying as ever when Echoes of the Eye sticks to the gameplay ethos that Outer Wilds established so strongly, while also pushing you're in new directions, and there's a surprisingly deep array of new wrinkles to the world that you'll need to expose in order to progress. The conclusion is thankfully strong enough to soften the blow the final third that precedes it, and it's made even better by the changes it makes to the conclusion of the main game, should you choose to see it through once more after the expansion. It wraps up the entirety of Outer Wilds in a way that just accentuates the strengths of the original ending without replacing what was there before, layering on a new sense of understanding to an existing, and immensely satisfying, conclusion.
That's what makes Echoes of the Eye unmissable if you couldn't get enough of Outer Wilds. It manages to push you in new, challenging directions with puzzles that scratch the same part of your brain that the original did while not relying on the same tricks. It's a feat that shows the depth of design prowess Mobius Digital first flexed in its debut title, but stumbles slightly when it tries to redefine its means of progression in the final third. These are the weakest moments in all Outer Wilds, but they aren't enough to sully what this fantastic expansion adds to an adventure that still stands as captivating and engrossing.
