Turns out the pure vessel wasn’t pure enough and had at least some semblance of a mind or will for the Radiance to control. Eventually the infection leaked out and infected even the deepest parts of Hallownest, leaving an utterly ruined civilization. This worked at containing the infection, for a time. Once the Hollow Knight was trained and ready the Radiance was channeled into him and he was locked inside the black egg behind the dreamer seal. The three dreamers entered a dream-like state and sealed the black egg with the hollow knight inside, prohibiting entry. The Pale King and the White Lady created several eggs together and dropped them into the abyss where void seeped into them, corrupting the offspring. The Radiance needs a host with a mind and will to control them, but a creature made of void would have neither of those things, making them resistant and immune. The Pale King learned void could be given form and decided to create what he deemed a pure vessel, a vessel strong enough to contain the Radiance. The Pale King’s palace was built under the city in a place called the Ancient Basin, and under the Ancient Basin is the Abyss with a lake of void, a dark substance that some ancient races worshiped. In order to stop the infection the Pale King and the White Lady hatched a plan.

The gates of the capital city were shut and so were the stagways, leaving many of the stags to die. Scholars from the Soul Sanctum took the soul (the life force that animates bodies) from countless bugs in an attempt to purify themselves, but they failed and grew mad from the power of all the souls. Most mantises could stave off the infection but other took it in willingly since it made them stronger. The creatures of Hallownest had different approaches to this problem. Some infected bugs grew large orange pulsating cysts on their bodies. This infection turned them mad and made them attack other non-infected bugs.

Also all of the citizens are insects or insect-basesd creatures. The goal of the game is to defeat the Hollow Knight who’s hosting a malicious entity called the Radiance that’s infecting the denizens of Hallownest with a disease that turns them mad. As you travel you unlock upgrades that give you abilities to reach other parts of the map, you can find charms and spells that give you fighting abilities, and the core components are parkour exploration and fighting enemies. You play as The Knight, nicknamed Ghost, who enters the kingdom from the outside and traverses it. For a little bit of backstory the game takes place in Hallownest, a shell of a former kingdom left to ruin. Item descriptions and NPC interactions help give context, and when one begins analyzing the map and characters met along the way the pieces of the puzzle slowly slot into place. There’s a lot the player does to complete the game, but the why is often unspoken. The game very much leaves the worldbuilding up to the player.

Hollow knight map of hallownest