Hollow Knight's narrative picks up the story long after the fall of the Kingdom of Hallownest. Since then, many of its denizens have fallen prey to the Infection that robs them of their minds and reanimates the dead.
With the loss of its people, so too went much of the anecdotal information about the key figures and goings-on from the lost civilization. However, there are bits here and there we can piece together to get a better understanding of this forsaken kingdom.
One group whose history has been particularly shrouded in mystery is the Five Great Knights. Here's what we do know about them.
Who Were the Five Great Knights?
The Five Great Knights were a small group of bugs that were chosen to be the Kingdom's defenders by the Pale King, who once ruled over Hallownest before the Infection. Each exhibited unrivaled heroism and combat mastery. The Pale King thus sought council with them, tasking them with missions no other could succeed at. Names of these grand historic events still linger in the air, such as The Battle of the Blackwyrm, though not much is known about them.
Standing beneath his throne, this diverse group attracted the awe of Hallownest's people, and those select few who've managed to survive the Kingdom's downfall inevitably have a few things to say about them. But by the time of The Knight's return to Hallownest it is found that the Great Knights have either mysteriously disappeared, become reclusive shells of their former selves, or died some time ago.
Even Relic Seeker Lemm cannot dig out basic retellings of their appearances amongst the journals and tablets left behind, which even fail to ever mention them by their individual names. What little information remains of the Great Knights is indeed hard to find.
Hegemol
The Great Knight who made for the most foreboding sight was Hegemol. Known for his might and sense of humor, he donned an impressive full suit of armor which later ended up in the possession of the maggot that can be fought early on in the game within the Forgotten Crossroads. By dream-nailing this "False Knight" it's revealed that it stole the armor from the Knight while he was sleeping for personal gain.
Whether Hegemol was murdered in the process or went into hiding afterward is up for debate, but it seems as though the mace equipped by the Maggot was not used by the Great Knight himself. In fact, in all depictions of Hegemol, such as the statue of him outside the City of Tears, he is never shown wielding any weapon at all. This instead suggests that he was a brawler who only needed the armor to fight. Perhaps this then explains his disappearance after it was stolen.
Despite his stature, he was also said to be surprisingly soft-spoken. This, together with the fact that a Maggot was able to wield the armor, could be a careful hint towards the Great Knight having a more modest appearance beneath it all. With all DLC released for Hollow Knight, this mystery could be further explored in Silksong, the game's long-awaited sequel.
Dryya
The sword-wielding Dryya was described as 'fierce' for her combat might and was at some point tasked with protecting the White Lady in her gardens. Although she kept a tough exterior, the White Lady remarks that she had a caring side beneath all this.
It seems she was immensely loyal to the White Lady in the end, who was at considerable risk of being driven out or succumbing to the exiled Mantis Traitors who sought to claim her gardens as their own. Dryya held back swarms of these Mantis Traitors, preventing them from ever getting to the White Lady, but she, unfortunately, lost her life protecting her from them
Her corpse can still be found directly outside of the Queen's dwelling surrounded by the bodies of many Mantis Traitors. As the White Lady survived, it can be assumed that Dryya's last stand successfully frightened them off for good, though she was left mortally wounded. Sadly, the White Lady has no knowledge of the Great Knight's sacrifice and assumes that Dryya is still alive out there.
Originally, though, the complete opposite of this was planned. One of the game's early Kickstarter updates teased Dryya as a boss who was driven mad by the loss of her Queen. This boss fight is one of but a few things known to have been cut from the game and it left a considerable impact on the central narrative at play. In doing so, though, Team Cherry allowed for the Great Knight's heroism to remain well intact.
Ze'mer
One of the five that has survived the Infection and can still be encountered by The Knight is Ze'mer. Found hidden away from all civilization, Ze'mer can only be encountered after breaking through a secret wall in a hidden area in the Resting Grounds. Even after encountering her there, her history as a Great Knight isn't immediately obvious, however, and she is instead referred to as the "Grey Mourner".
As it turns out, Ze'mer was in love with the daughter of the Traitor Lord, though their courtship was not approved of by the members of the Mantis Tribe. At some point, though, her Mantis lover was somehow killed, which explains Ze'mer's grief-stricken mourning. It seems now that her lover's death is all that dominates her mind, so much so that Ze'mer tasks The Knight with a near-impossible task: to deliver a Delicate Flower to her partner's grave.
This flower, like Ze'mer, is not of Hallownest origin, but comes from the "Lands Serene." If The Knight manages to succeed in passing on this flower to the final resting place of her Mantis lover, Ze'mer is finally able to move on and dissipates into thin air shortly after granting the protagonist a mask shard. However, hardly any knowledge of her past beyond this romance is gained from assisting her, though a huge sword-like weapon by her side suggests she was a very capable defender beforehand.
Isma
Another Great Knight who has long since passed is Isma, though the circumstances of her demise are highly mysterious. Her overgrown remains can be found in her grove within the Royal Waterways. There, her body is ingrained with the wall, nearly completely encompassed by plant life, which makes the circumstances of her death rather confusing.
However, a 'tear' can still be obtained from Isma that allows The Knight to circumnavigate acid with complete immunity to its corrosive effects. This perhaps suggests that Isma's powers were tied to dominion over acid in some shape or form, with the popular theory being that she was a plant-bug hybrid like the Mosskin of Greenpath.
What is known of Isma though is that she and Ogrim had a very close relationship. This is evidenced by how Ogrim appears to be protecting her area specifically out of all of the nooks and crannies of Hallownest. Through dialogue with Nailmaster Sheo, it is revealed that she possessed a kind and understanding nature despite wielding power that surpassed Ogrim, who looked up to her immensely.
Ogrim
Although best known now as the Dung Defender, Ogrim was well-respected as a Great Knight and was said to be the most loyal of their ranks. He is one of the few who has survived the fall of Hallownest and can be found in the Royal Waterways where waste gathers. To access this area, a simple key is needed. Here, beneath the City of Tears, Ogrim gallantly fights The Knight after assuming them to be a Husk. Upon defeat, however, he is quick to apologize and recognizes them as a friend to the Kingdom.
In defending Isma's Grove, Ogrim showcases how his loyalty to the others remains staunchly intact. In fact, he has sadly deluded himself into believing that they are all still alive, along with Pale King, though he speaks of an unknown oath that prohibits him from seeking them out. Despite this, he is extremely nostalgic about their time together, and accessing a secret area beneath his lair reveals that he has made dung statues to commemorate the others.
Ogrim can be challenged again in a string of dream battles. Simply returning to the area where he is found after defeating the three Dreamers. Here, within his fond dreams of yonder, Ogrim is depicted at the height of his power and impressively clad in a royal white variant of his armor. This could perhaps indicate that the other Great Knights donned white when in the Pale King's audience or servitude.
Beating him like this five times perhaps breaks Ogrim's spell as he then promptly disappears from the area. He does, however, leave behind one last dung statue of The Knight who he now recognizes as an equal and one of Hallownest's greatest heroes.