Hellblade: Senua’s Sacrifice uses everything in its arsenal to perpetuate feelings of dread, anxiety and fear: camera perspective, light, sound, visuals, combat. There are no scary monsters, no jump scares, none of the traditional horror fare. Instead, it taps into something infinitely more terrifying: human psychology. And it is wildly successful.

Developer Ninja Theory worked alongside a team of mental health specialists, professors of psychology and people recovering from psychosis to convey their experiences. The depiction of main character Senua’s hallucinations and delusions feel vivid, honest and terrifying. From seeing literal fragments of reality to wandering mazes guided by a grieving ghost, every little thing you do skirts the line between myth and a terrifyingly inescapable reality. Every battle and puzzle ties back into the underlying themes and experiences of psychosis.

I was far more disturbed at what I was hearing than what I was seeing

The game opens with Senua, a Celtic warrior with severe psychotic mental illness, returning to her village following a Viking raid. After discovering that her lover was sacrificed to Norse gods, she embarks on a vision quest to retrieve his soul from them. Throughout the entirety of Hellblade, she carries his skull wrapped in cloth, unwavering in her quest to bargain with the Norse goddess of death, Hela.

As the opening credits roll, Senua paddles past burned and staked corpses. It isn’t long before the whispers start. They get progressively louder, creeping into your left ear and then through to your right. Suddenly, the whispers are all around you, and it’s impossible to tell how many people are speaking all at once.

Hellblade’s 3D binaural sound is easily the best — and scariest — part of the game. Several voices are present almost all the time with no real sense of identity, including the narrator’s. I was cheered on, degraded, laughed at, cautioned and questioned to no end. As the voices came at me from all sides, I felt myself slipping out of my bedroom and into Senua’s world, one where there is no quiet or rest.

Ninja Theory is absolutely masterful at tapping into the childlike fear of what might be hiding in the dark

Clever use of sound plays a greater part elsewhere in the game as well. At one point, Senua undergoes a trial where she gropes in the darkness for 10 minutes. I was required to only use my sense of hearing to navigate through to the end. Echoing footsteps somehow transformed into something more sinister. A deep layering of inhuman growling signaled that there was something else in the darkness with me. I was far more disturbed at what I was hearing than what I was seeing. The game is absolutely masterful at tapping into the childlike fear of what might be hiding in the dark.

Hellblade does a thorough job at saturating other mundane moments with anxiety. Even equipped with a sword, I still felt vulnerable when exploring a new area. It doesn’t help that there is no combat tutorial of any kind, and no HUD to speak of. In fact, the game provides you with only one prompt: Every time you die, rot progresses up Senua’s arm. When it reaches her head, she will really die, and all progress will be lost. It’s a cruel and unforgiving mechanic, and it was successful at adding a thick, heavy layer of tension and hesitation into everything I did.

Surprisingly, I noticed that the threat of growing the rot didn’t apply to boss fights, but did for environmental deaths. Was the threat of erasing all my progress a lie? I’m not sure. But even if it was, it fit perfectly into the narrative of Senua’s reality, where curses and Hell are very real.

How many “lives” or how much health I had left was always a mystery in Hellblade. The only hints are increasing distortions of the screen. The basic controls were easy enough to figure out; precise evasion and timing your light and heavy attacks are key to winning battles against slow-moving, powerful enemies. At times, I ran into horde-style encounters where enemies appeared in waves for a set period of time. After a short while, attack patterns became predictable and easy-to-read. The waves weren’t exactly strategically challenging — they only required fast reflexes.

But even in combat, the game layers on metaphor after metaphor. Sometimes I found myself feverishly hacking away at a boss for what seemed like an hour until wisps of smoke suddenly replaced rotting flesh. Senua swung at nothing, powerless until I could activate her “focus” ability. When the battle was finally over and I relaxed my grip, the boss came back out of nowhere, grabbed Senua by the ankles and dragged her to the floor. It became abundantly clear: There is no rest when it comes to inner demons, and Hellblade sticks to this theme this in its brief but palate-cleansing battles.

Fix a broken bridge by looking at shards of reality from just the right height or angle

To my surprise, the frequency of puzzle-solving overtook fighting in Hellblade. In a 25-minute bonus documentary feature that’s included with the game, titled Hellblade: Senua’s Psychosis, psychiatrist Paul Fletcher says that “people begin to see patterns in the world. They begin to link things that most people wouldn’t.” This is the underlying theme of all Hellblade’s puzzles. Solving them requires broadening your perception, paying attention to the environment and finding patterns.

To unlock certain doors, you’ll need to look at a rune and find something in the environment that matches it. It could be the shadow of a beam cast onto a wall or a hanging branch that aligns with a pole. Fix a broken bridge by looking at shards of reality from just the right height or angle. It’s all about finding the right vantage point and seeing the world in a way different than you normally would. This is one of the strongest ways in which we can understand how Senua copes with her illness. Video games are able to more clearly convey this in ways that film or books cannot. These segments gave me a window through which I could see and interact — to the best of my ability — what a warped reality feels like. And within those literal shards of reality I saw floating in the air, I learned that there were always threads I could pick up on that would lead me back to a calmer place.

Solving these puzzles of perception quickly became one of my favorite parts of Hellblade, but at times they staggered the flow of the game. Riding the adrenaline high of decimating a horde of enemies can be quickly extinguished by having to thoroughly comb through an area multiple times to find a semblance of a shape. If you can’t find the rune, you can’t advance through to the next part of the map. It can sometimes feel like a bit of a grind, especially given how Hellblade reads as more of an experience than a game in almost every other respect.

WRAP UP

Hellblade is both a psychological terror and an enlightening experience

Hellblade is not an Orphean quest to retrieve a dead lover from the underworld. It’s not some epic tale of revenge. It’s an education and contextualization of being psychologically different in the time of Vikings and Celts. Nearly every facet of the game — whether it’s combat, puzzles or exploration — is deliberate, pointing back to the overarching theme of what people called “cursed” during that time. Hellblade successfully weaves metaphors of grief and loss into fundamental game mechanics and rich folklore, and through these I felt like I truly was able to understand how someone else sees the world.

Hellblade: Senua’s Sacrifice was reviewed using a “retail” PlayStation 4 download code provided by Ninja Theory. You can find additional information about Polygon’s ethics policy here .