The World Design of Hollow Knight | Boss Keys

If you were a fan of Metroidvania games, then 2010 was a very difficult year. On the one side, we got Metroid: Other M - a game that paid lip service to exploration and isolation, but was way more interested in action-packed fights, cringe-worthy cutscenes, and excessive handholding. And on the other side, after six cracking Castlevania adventures on handhelds, we got Castlevania: Lords of Shadow - a knockabout brawler that took most of its inspiration from God of War, and had only the lightest hint of exploration.

It looked like the Metroidvania was dead. Except, it really wasn’t. Because while Nintendo and Konami were about to drop off for a decade-long slumber with their respective franchises, other developers - especially smaller indie studios - were starting to try their hand at the Metroidvania formula. Cave Story, Aquaria, and Shadow Complex were early attempts to follow that recipe of locked doors, new abilities, grid-like map systems, and secret items.

And since then we’ve seen games as varied as Strider, Axiom Verge, the Shantae games, Toki Tori 2, Guacamelee, Headlander, and Ori and the Blind Forest. But none of these games would quite prepare us for one that was released in 2017. This is a masterpiece, with crunchy combat against imaginative boss monsters, crushing Dark Souls-esque difficulty spikes, a deep well of lore that would launch several YouTube careers, and - most important of all - an elegantly designed, interconnected world that is just a joy to get lost in.

So this is Boss Keys, and today - join me on a deep dive into the world design of Hollow Knight.

Hollow Knight takes place in the sprawling kingdom of Hallownest. The game begins in Dirtmouth: a fading town with a few shops and visiting adventurers. Beneath that lies the Forgotten Crossroads, which - as the name might suggest - connects up to many areas in the game, including the leafy suburbs of Greenpath, the deadly mines of Crystal Peak, the acidic Fog Canyon, and the noxious caverns of the Fungal Wastes. In the very depths of Hallownest you’ll find the pitch-black labyrinth of Deepnest, and the mysterious Ancient Basin.

While in the furthest corners you’ll discover the graveyard, called the Resting Grounds, the Howling Cliffs, and the lush greenhouse of the Queen’s Gardens. And at the kingdom’s edge you’ll find the, uh, Kingdom’s Edge - which also connects to The Hive. All of these areas surround the enormous capital of Hallownest: the endlessly-drenched City of Tears, and its Royal Waterways sewer system. Together, these 15 different zones create a jigsaw of neatly fitting puzzles pieces.

Now, each area is visibly distinct. There’s no confusing the pink gems of Crystal Peak with the leafy green walls of Greenpath, or the candlelit blue walls of the Forgotten Crossroads, or the muted greys of the Ancient Basin. It’s especially helpful that the colour of each area matches the colours on the map. This all makes it easy to keep these areas separately catalogued in your brain box, enormously helping with navigation and spatial reasoning.

But you’ll also find gameplay differences in each zone, which keeps them fresh and varied. That includes bouncing on trampoline shrooms in the Fungal Wastes, dodging laser beams in the Crystal Peak, and peering through the darkness in Deepnest. Some areas, like the Kingdom’s Edge, are vertical in nature - while others, like the Royal Waterways, are stretched out highways. And there are also unique enemies in each zone - like exploding bugs in Greenpath, kamikaze jellyfish in Fog Canyon, icky spiders in Deepnest, and cute bee-lets in The Hive - which makes every zone feel brand new.

When we first drop into Hallownest, we’re not exactly given any real goal or direction. This first cutscene shows a lone wanderer - the mysterious Knight - just kinda rocking up to the kingdom and jumping on in. But we are given some vague hints about where to go. The Elderbug in Dirtmouth tells us to head on down. And this sign in the west end of the Forgotten Crossroads points towards “the city at this kingdom’s heart” - a place where “all wishes shall be granted, all truths revealed”, apparently.

Sounds like a good place to check out, if only it wasn’t guarded by an invincible armour-plated beetle. Something Hollow Knight does well is to hint at upcoming areas with one room that shares that zone’s visual identity - like the rooms in the Forgotten Crossroads that have leaves from Greenpath, or gems from Crystal Peak. This is a great way of teasing future content - and lodging that place in the player’s brain as somewhere worth returning to.

In the centre of the Forgotten Crossroads is a big ol’ boss called the False Knight - and behind him is our first power-up: the Vengeful Spirit, which is a sort of Hadouken-style blast. In the tutorial for this new ability we use it to defeat another armour-plated beetle, reminding us to return to that corridor, and make progress to Greenpath. This is a Metroidvania after all - so expect to find locks and keys. Here, in Greenpath, we meet Hornet: who keeps dashing just out of view - and acts like a carrot-on-a-stick to lure us over to the west side of the area.

There, we’ll summarily dispatch Hornet - hopefully, she’s pretty tough - and get the second upgrade: the Mothwing Cloak. This lets us dash in mid-air, granting access to the Fungal Wastes. We’re still being teased by that city - thanks to literal signposts that point the way down. And Hornet does her little carrot-on-a-stick routine once again, as she darts towards the city’s entrance. Not that you can follow her, mind you, due to the bridge being down.

So instead, we enter the Mantis Village, and find the next power-up: the Mantis Claw. This allows us to scale up walls and is the perfect ability to get us past that bridge and - finally - into the City of Tears. So, at this point, Hollow Knight seems quite linear. We’re following a standard sequence of upgrades and boss fights, and following a critical path through Hallownest. But if the game’s developers were leading us to the city by the hand - if only quite subtly, with vague clues and in-world signposts - then this is the point where they let go.

At the centre of the city, we’ll meet Hornet once again - and she’ll tell us to visit "the grave in ash", but there’s no indication of where that is. And while the fountain actually puts a marker on our map for the first time in the game - it’s for the Black Egg Temple back in the Forgotten Crossroads, which is somewhere we’ve already been, and that thing’s locked up tight. So the question is - where to next? Let me back up a bit.

If we look at the map of Hallownest, and reveal how much of the world we can explore at each point in the game, we can see that our initial reach is limited to just Dirtmouth and the Forgotten Crossroads. After we get the Vengeful Spirit, we can go a smidge further, into Greenpath and the Fog Canyon. And the Mothwing Cloak reveals a tiny bit more for us to see still, letting us into the Fungal Wastes. But as soon as we have the Mantis Claw, the map is massively unveiled to us - we can go to the City of Tears, of course, and - provided we’ve found a Simple Key - the Royal Waterways.

We can pop up to the Howling Cliffs, descend into Deepnest, or check out the Ancient Basin. We can even reach the Resting Grounds. And if we discover the Tram Pass in Deepnest, we can also visit the Kingdom’s Edge. And this was definitely a deliberate choice by the game’s developers. I spoke to Ari Gibson and William Pellen from Team Cherry over email, who told me this: “we started with a basic, linear progression of item acquirement, with the idea that we would allow that progression to break apart, branch out and wind around itself as the world grew.”

So while our journey has been quite constrained up until now, there’s suddenly a bunch of different things we can do all at once. We can go fight the Dung Defender in the Royal Waterways, which lets us flip a mysterious switch. Or we could challenge the Mantis Lords, to open up access to Deepnest. Or we could go fight the Soul Master in the City of Tears, and get his handy Desolate Dive ability. That lets us into the Crystal Peak, and allows us to pick up the Crystal Heart: a sort of bonkers jet-powered super dash, which opens up a lot more areas.

That includes a place in the Ancient Basin where we fight the Broken Vessel and get the double jumpin’ Monarch Wings. And also an area in the Royal Waterways, where - provided we hit that switch earlier - we can pick up Isma’s Tear, which lets us splash about in acid water. So, by opening up the world in such a dramatic fashion, Team Cherry doesn’t actually need to lead you by the hand anymore. Because if there are loads of different things to find all over the map - the player will likely stumble upon something important, no matter which direction they take.

Now, I should say that after entering the City of Tears, the developers ideally want you to go fight the Soul Master and get the Desolate Dive ability. They even slam the city’s gates shut behind you - and the only way back through is to smash through this floor with - you guessed it - the Desolate Dive. This is a classic Metroidvania trick of locking the door behind the player, so they don’t back out without finding the necessary goodies.

But something you should know about the world design of Hallownest is that there’s always more than one way to go. For example - remember when I said you need to fight the Mantis Lords to gain access to Deepnest? Well, not necessarily - because if you find this semi-secret path in the Fungal Wastes, you can get to Deepnest from there and bypass that boss fight altogether - providing two routes to the same place. Also, you can get to east side of the City of Tears through the Royal Waterways.

Or by taking a lift down from the Resting Grounds. Or by taking the tram from Deepnest to the Ancient Basin, and climbing back up to the city from there. Or you could even come in via the Kingdom’s Edge. That’s four routes to the same place. The Crystal Peak is another key area for this. For starters, there are multiple routes through this zone when getting to the Crystal Heart, allowing us to skip this Crystal Guardian boss fight altogether if we so wish.

And there’s two routes into the mine itself. Before, I mentioned using the Desolate Dive to smash through this floor - but there’s also this pitch-black and seemingly inaccessible room in the Forgotten Crossroads. Come back with the Lumafly Lantern from the shop in Dirtmouth, though, and you’ll be able to see that there’s actually a gate in that room. Once unlocked, you’ll get access to the Crystal Peak. And if you’ve got the Mantis Claw, you can even hop up and get the Crystal Heart, meaning you can bypass the Soul Master and his Desolate Dive pick-up altogether, if you so wish.

The explorable area following the Mantis Claw actually looks like this, then. In fact, because you can reach this dark room at the very start of the game, you can theoretically enter the Crystal Peak before getting the game’s very first power-up: the Vengeful Spirit. Though, at 1,800 Geo, the lamp is rather expensive and will be hard to save up for at this very early stage in the adventure. It’s an interesting example of a what we might call a “soft lock”, though: a route through a game that isn’t physically inaccessible to the player, but will turn most adventurers away at this early stage because they’re not yet strong enough, don’t have enough knowledge, or - in this case - don’t have enough cash.

So while the door to the City of Tears does shut tight behind you, there’s plenty of creative ways out of the city that don’t require the Desolate Dive ability. Providing multiple routes through the game certainly allows you to pick your own path during the adventure - which is perfect for second playthroughs, speed-runs, low percentage challenges - and most importantly of all - a feeling of legitimate agency. Because - similar to games like Dark Souls and the very first Metroid and Zelda games - the route through the game is dictated by your own curiosity and sense of adventure.

But this is also a wonderful way to stop the player from getting stuck. Like: think about the Grapple Hook in Super Metroid. It can be used to access loads of places around Zebes but most of them just lead to inessential upgrades like the Wave Beam and Energy Tanks - so let’s call these optional locks. Only one Grapple Hook point actually allows further progress through the game, towards the Wrecked Ship - so we might call that a critical lock.

And so while you’re certainly going to get loads of cool goodies to upgrade Samus, it does mean that if you can’t find that one single critical lock, you’re going to be stuck. In Hollow Knight, though, things are a bit different. Like, after getting the Mothwing Cloak from Hornet in Greenpath, there are loads of places to use it. Some lead to handy pick ups. But also, you can dash up here in the Fog Canyon’s Queen Station, and dash up here in the bottom of the Forgotten Crossroads - and both lead you to the Fungal Wastes, and continue your adventure towards the Mantis Village.

Having two critical locks instead of one dramatically increases your chances of making progress through the game. Because whether you remember some past blocked-off area and decide to backtrack to it with your new power-up, or you just continue adventuring onwards and hope to stumble upon the next part of the game - you’re much more likely to make progress if there’s more than one critical lock to find. This is a technique that’s used to great effect in the Resting Grounds.

Some players will drop down into the area from this chasm in the Crystal Peak. But others might, instead, find the Tram Pass in Deepnest and ride a train car from the Forgotten Crossroads over to the Resting Grounds. They might take a lift up from the east end of the City of Tears, and reach the Resting Grounds from underneath. Or they might get to that same entranceway, but by using the Crystal Dash to get to the Blue Lake.

That’s four completely different paths to the same area - using all sorts of different abilities and routes. And it can be accessed from the very start of the game, if you take that route through the pitch-black room I discussed earlier. But this is all for a reason. The Resting Grounds is actually the “grave in ash” that Hornet spoke of back in the City of Tears, and it’s one of the most important areas in the game because it finally gives us an actual goal - we need to take this Dream Nail and use it to wake up three sleeping sentries: Herrah the Beast, Lurien the Watcher, and Monomon the Teacher.

So by having all sorts of different ways into the Resting Grounds, Team Cherry can be sure that players will almost certainly get there eventually - but they don’t have to be led by the hand using signposts, directions, or map markers. Instead, you just get that wonderful feeling of “accidentally” stumbling upon something really important. Team Cherry says it tried to avoid using too much signposting because it would be “to the detriment of many players who, through initially being lost, find their own ways and begin to learn the layout of the kingdom on a much more personal level”.

There is one exception to that, though: when you look at this statue in the Resting Ground, the dreamer’s masks are drawn onto your map, marking the location of these characters. And normally, I’d be kind of against this sort of overt and gamey direction. However, this turns out to be less of a bunch of nagging waypoint markers and more of a gentle reminder of what your overall goal actually is. Because, your map is likely so uncharted that these masks are just floating in an unhelpful sea of black, and you almost certainly don’t have all the abilities to actually reach these dreamers yet.

Herrah, for example, is hidden away in her den in the furthest corner of Deepnest. You’ll need the Mantis Claw to get in there, and the Lumafly Lantern to actually see what you’re doing. Lurien is high atop his spire, overlooking the City of Tears, and can’t be reached without the Monarch Wings. And you’ll need to defeat the Watcher Knights at his door. And Monomon’s kipping in her archive in the Fog Canyon, which is blocked off unless you have Isma’s Tear.

You’re also going to have to dispatch the rather familiar looking boss, Uumuu. So while the masks on your map might point out the final destinations, they don’t tell you anything about the many stops you’ll need to make along the way.

There’s one final way that Team Cherry allows you to dictate your own path through the game, and that’s by allowing, encouraging, and even designing in tricks that allow you to get past obstacles without the necessary upgrades. Similar to tricks like the wall jump in Super Metroid. So you can use the kickback blast of the Vengeful Spirit to propel yourself to areas that would normally require the Mothwing Cloak. You can use the Crystal Heart to bypass bits that need Isma’s Tear.

And most disruptive of all, you can bounce off background decorations and flying enemies with the nail to give you an extra lift - and render the Monarch Wings technically optional. Now that’s what I call exploiting a bug! Team Cherry told me that “we knew players would be able to sequence break using the nail bounce technique, and we absolutely wanted them to be able to do so. Watching players discover new routes is a huge joy for us and is a really empowering moment for a player.”

“We even placed certain enemies and objects to allow some shortcuts” - though, they admit that “the Hollow Knight community has uncovered many more skips that we’d never considered ourselves”. One spot in the Kingdom’s Edge had to be fixed in a patch, as it was possible to get yourself stuck if you managed to access it before acquiring the Monarch Wings. With all three dreamers awake, we can now finally enter the Black Egg Temple in the Forgotten Crossroads, fight the, ahem, final boss: Hollow Knight, and ahem, finish the game.

Now while I normally like to use graphs to explain the structure of Metroidvania games on Boss Keys, it’s not really possible with Hollow Knight. So much stuff can be be skipped, or done in different ways, or reached from different directions, that creating a single, monolithic chart for the game’s structure is just not possible. I can show you one route through the game, though, which at least reveals the general shape of things.

Essentially, a linear corridor of upgrades and boss fights, which dramatically fans out to a wide open matrix of non-linear possibilities. Including the ability to pick up game-changing abilities simultaneously - which is something you don’t usually see in Metroidvanias, because they often dictate a more set-in-stone sequence of getting one item after another. But Team Cherry says “we wanted players to feel like their journey through the kingdom was their own, and part of that was removing barriers or opening paths to allow acquiring items or powers ‘out of order’.”

Of course, this graph has a million different permutations. You can skip the Mantis Lords and the Crystal Guardian with careful navigation of the map, get the Dream Nail much earlier in the game, reach the Crystal Heart without the Desolate Dive, and so on. But beyond that, there’s so much more that this graph doesn’t even begin to cover.

For starters, while I’ve already talked about the bosses that are standing between you and the game’s credits - there’s also bunch of completely hidden bosses that have no impact on the structure of the game whatsoever. There’s the Brooding Mawlek, who’s in a hard-to-reach room in the Forgotten Crossroads. The Collector, who can’t be found unless you get the Love Key from the Queen’s Gardens. The Enraged Guardian, who’s hiding in a secret room above the other Guardian’s boss area.

The Flukemarm, who can only be found if you use the Desolate Dive in the Royal Waterways. And Nosk, in Deepnest, who can only be reached with either the Crystal Heart or the Monarch Wings. There’s also the Hive Knight in, I'll let you guess, but he’s exclusive to the Lifeblood DLC. And there are more bosses beyond these. At the Kingdom’s Edge, you’ll find the Colosseum of Fools - which is a non-stop combat gauntlet, with a handful of unique bosses.

And the seven Warrior Dreams, who are ghostly spirits that are are guarding their gravesites, and can be challenged to a dual after you acquire the Dream Nail. And dream variants of the Broken Vessel, False Knight, and Soul Master bosses - which are like super hard remixes of those fights. Two more come in the Hidden Dreams DLC, as well. Ultimately, it is quite incredible to stumble down some random hallway, and not just uncover a handy item or whatever: but an entirely unique boss fight that some players might never see.

Team Cherry says it doesn’t worry too much about whether everyone will find the content it makes. “Just having it there, out of sight from most players makes the world more truly alive,” the developer explains - “much of it exists to convey a sense that there’s always something else waiting in the unexplored recesses of the world - fearsome enemies, strange characters, new areas, powerful items etc.” “And [it] creates a very special experience for those few that do make the discovery.”

So depending on how you categorise things, and whether or not you include the Lifeblood and Hidden Dreams DLC, there are more than 30 bosses in the world of Hollow Knight, but you might only fight about 10 to 15 of them during your adventure. It’s crazy. An absolute butt load of extra bosses and remixes are added in the other two DLC packs: The Grimm Troupe and Godmaster, but they’re not relevant to the normal exploration of Hallownest, and so I won’t be discussing them in this video.

What’s the point of going after these non-essential bosses, then? Other than the fact that you don’t actually know which bosses are necessary to beat the game, of course. Well, it’s all about 'dem goodies. The world of Hollow Knight is jam packed with stuff to find - sometimes hidden behind bosses, sometimes behind secret walls, sometimes behind those optional locks, sometimes as expensive items in shops, sometimes just found off the beaten track.

You’ve got your usual upgrades: 16 Mask Shards act like the heart pieces in Zelda: so find four of them and you’ll be able to take an extra hit in combat. The 9 Vessel Fragments are kinda similar: find three of these and you’ll boost your available mana for powerful spells and recharging your health. There are also special moves, like the Great Slash, Dash Slash, and Cyclone Slash. Soul upgrades like the Abyss Shriek and Descending Dark.

And you can boost the power of your Nail if you find Pale Ore. And then there are the charms. These collectable badges give you all sorts of handy abilities like quicker recovery on your spells, no knock-back when fighting enemies, and so on. Every one is uniquely interesting to equip and they even synergise for more abilities - but are limited to the number of charm notches you have. And yes, you can find charm notches as well.

All of these items are well worth finding because Hollow Knight is definitely not an easy game. In fact, it’s brutally difficult at times, has the same find-your-corpse-when-you-die mechanic as Dark Souls, and some of the bosses just do not mess around. That makes getting more health, or a charm that can help you in combat, or a boost to your nail’s strength, or a more powerful spell a genuinely worthwhile thing to find.

Defeating some hidden boss doesn’t feel like a waste of time because it didn’t let you make any progress - the reward is usually useful (or, at least, interesting) enough to make your efforts feel worthwhile. I do want to say one thing about the corpse run mechanic, though: this is one way that Hollow Knight sadly discourages exploration through its design. When you die in, say, Zelda 1 - it’s easy to say “you know what?

Screw that area, I’m going to look somewhere else”. When you die in Hollow Knight, though, you drop a shadowy clone of yourself - who hangs on to all your money and limits your mana amount to half. This tempts you to return to the place you just died - sometimes over and over and over again - regardless of the many other interesting places you could explore, or different routes you could take. These extra bosses and endless special items also make you feel like there’s something to find around every corner.

No matter where you explore, there will be something to find. Sometimes it’s not even relevant to the gameplay at all - it’s just story stuff that adds to the rich and immersive atmosphere of the game. My personal favourite take on this is the way certain characters seem to be off on their own little adventures. Bugs like Cloth, Quirrel, and Tiso, keep popping up all over the place - each commenting on their status and location.

It makes the world feel alive, and less like the game revolves entirely around the player. These bugs are off doing their own thing, with our without you. One bug who definitely does need you, though, is Zote. This arrogant dude can be found in the mandibles of a Vengefly King in Greenpath - and it’s up to you if you save him. Same goes for when he’s later found stuck in spider webs in Deepnest. If you save him both times, he’ll appear as a boss - of sorts - in the Colosseum of Fools, and then in Bretta’s house in Dirtmouth.

But if you miss him in Greenpath or Deepnest, or simply choose not to save him - well, that’s it. That whole quest will just not happen - and once again, proves that Team Cherry doesn’t care if you see their work, because it makes it all the sweeter for those who do witness the full story. The game is actually packed with little quests like this, such as a mission to save the Grubfather’s children, a promise to fill out of a journal of every enemy in Hallownest, a tricky quest to carry a delicate flower across the map, and a personal favourite: the way a secret stag station opens up when you unlock all the other stations.

All of these help flesh out Hollow Knight’s rich narrative, and add memorable character moments. The world itself tells stories, too. My favourite example of this is the Blue Lake, which is positioned above the City of Tears, and explains why the city is constantly raining. Amazing.

Let’s talk about actually getting around Hallownest. So we’ve already discussed the multiple entry points between areas in the game. In fact, every single zone, except for The Hive, is connected to at least two other places in Hallownest, through lifts, passageways, tram stations, and secret routes. Team Cherry says “It was always intentional to give players different ways to travel to and through (and sometimes around) areas.”

Some of these were planned ahead of time, but others were added when the opportunity presented itself - “For instance, when Deepnest grew tall enough that the top of it was brushing against the bottom of the Queen’s Gardens, we added a connection between them.” “If we can add a connection between adjacent areas, and it makes sense in the world, and it doesn’t cause players to get stuck somewhere, then we do it”. But when playing the game, many of these routes start out as only going one way.

So it’s initially impossible to get from Dirtmouth to Crystal Peak. But after getting the Crystal Heart, you can zoom along here and open up a lift between the town and the peak. It’s one of those wonderful “aha” moments you get in such elegantly designed wrap-around worlds, like taking that first elevator back to Firelink Shrine in Dark Souls. What this means is that Hollow Knight’s developers can initially restrict your access to certain places - to create a semblance of order and sequence to the game’s items.

Like how you need the tram pass to get to Kingdom’s Edge. But then by opening up new routes from the other side, like this path through to a lift shaft in the City of Tears, the game’s world becomes far easier to navigate. Team Cherry does this in micro-form, too. Take the Forgotten Crossroads, where this locked gate blocks off easy access to the boss. Instead, you’re forced to go all the way around the zone, taking in every room and challenge along the way.

However, once you unlock that gate it becomes permanently open - giving you easy passageway through the crossroads. This is a clever way of ensuring that the first time a player enters a zone, they are forced to tackle difficult challenges and set-ups. Things like tricky platforming sections, or areas with tough enemies, or brutal gauntlets against waves of foes. But once you’ve proven you can do it once, you’ll be able to skip this stuff during revisits to the zone - massively reducing the boring bits of backtracking.

There’s only a few times where Team Cherry breaks this rule. At some point in the game, the Forgotten Crossroads gets taken over by these malicious orange bubbles and becomes The Infected Crossroads - complete with new, harder enemy types. Now, I do love this: it makes the world feel changeable, like time is not standing still during your adventure. And it makes one of the earliest parts of the game - which has started to become a cakewalk with your newfound skills and abilities - a new source of challenge.

But it also blocks off a couple routes through the zone, making it just slightly more annoying to navigate. Grr. I should definitely also mention the Stag network. Similar to the fast travel points in Castlevania: Symphony of the Night, these stag stations are dotted around Hallownest and provide easy access between some of the zones. With a map the size of Hallownest, I think these fast travel points are a fine addition - it would be horribly tedious to get about without them.

And besides, with two stag stations in the City of Tears, only nine of the fifteen areas have stations, so there’s not enough to just let you teleport all over the place. You’ll still need to know your way around, and carefully plot your journey out on your map.

Oh, the map! Gosh, how has it taken this long to talk about one of Hollow Knight’s most interesting features: its mapping system. So, when you first start the game you won’t have a map of the world at all. But then you’ll come across this cheeky chap: Cornifer. He’s a cartographer who will sell you his sketchy, incomplete maps of each zone in the game - these kind of work like the map stations in Super Metroid, which hint at places you can explore and interesting areas you should check out.

The map for the Forgotten Crossroads, for example, has a drawing of a big scary monster head, which points you in the direction of the game’s first boss. Back up in Dirtmouth, you can buy a quill which then turns the map into a more traditional auto-mapping system. But with a couple twists: one is that the map only fills in when you sit down on a bench to rest. And the other is that in order to see your position on the map, you need to buy and equip a compass charm - handy, but maybe it would be better to use that slot for something else?

A decision you can make. The way a game chooses to reveal its world on a map can completely change your experience with exploring that world. Classic adventures like Zelda and Metroid didn’t have maps - likely due to technical limitations, but it created this real sense of mystery and unchartedness, and forced you to make your own map, either in your head or on paper. The Souls games would revisit this idea much later, forcing you to forge a map of places like Lordran or Yharnham in your bonce.

But a good, clear map is handy, too. It’s nice to plot out routes you want to take, it can help you figure out where you have and have not yet explored, and it’s great for scooping up items and secrets. Hollow Knight gives you the best of both worlds. When you first enter a zone, your map is completely blank - you’re stumbling in the dark, and you have no idea about the size and scope of the place you’re in. It makes new places feel scary and dangerous.

Then, when you get the sketchy map from Cornifer, you get a slightly better idea of where to go - and some hints at places you might want to check out. And then once you sit in a bench, you get the full map. You can see more clearly how the world is laid out, plan routes through Hallownest, and if you’re feeling a bit stuck - scan the map for paths you’ve yet to venture down.

So, if you thought the final cutscene in Hollow Knight was a bit anticlimactic - you’d be right. Like many Metroidvanias before it, Hollow Knight has a bad ending - and a whole lot of gameplay to go if you want to get the true, good ending. Here’s the basic run down: you need to hop up here in the Kingdom’s Edge, fight Hornet for the second time, and enter the Cast-Off Shell. Inside is the King’s Brand, which can be used in the Ancient Basin to open up a big ol’ door and grant access to The Abyss.

Inside is the Shade Cloak, which finally lets you bypass a recurring obstacle in the game: these black geysers of toxic goop. By the way, you can use the shade cloak to get to the teacher’s archive from a different direction and wake Monomon without fighting the Dung Defender or getting Isma’s Tear. Cheeky! Anyway, one black geyser blocks a new boss fight: the Traitor Lord. And the prize for beating him is the White Fragment. Sweet.

Now, there’s a character called Seer in the Resting Grounds who will give you goodies in exchange for Essence, which is gained by defeating the Warrior Dream bosses, the dream variant bosses, using the dream nail on ghosts, and collecting Essence spawned from whispering roots. If you gather 1800 of this stuff, Seer will upgrade your Dream Nail to the Awakened Dream Nail. Now if you use this on a corpse in the Ancient Basin you get to go to the White Palace: a nightmare hellscape void of misery that’s as hard as anything in Super Meat Boy or Celeste but, like, without the super sharp platforming controls of either game.

God damn this bit is quite annoying. At the end though is another White Fragment. Stick them together and you’ve got the Kingsoul. And then return to the Abyss and you’ll turn that into the Void Heart. Finally, return to Hollow Knight and use the Dream Nail on that dude to enter his brain and fight the actual proper last boss: Radiance. Who is very hard and makes me want to cry. But I did it. After like a million goes.

I’m quite amazed just how much content there is in this secretive end game. It took me about 20 hours to get to the credits for the first time - and then another 10 to get to the proper ending. Testament, I guess, to how Team Cherry is happy to let players just miss huge swathes of content. Now, personally, this bit didn’t quite work for me. I felt finished and satisfied with the game after dispatching Hollow Knight for the first time.

And when I discovered that there was a lot more to do, I didn’t really have the drive to carry on and seek out yet more secrets. Especially because I had no idea where to go. And the game doesn’t keep up that tradition of offering two routes into key places so if you miss this jump in the Kingdom’s Edge, you won’t get very far. Basically, I just followed a walkthrough to get to the true final ending. Bit of a let down.

So, that is Hollow Knight. The game helps lure you into the world of Hallownest with cryptic clues and the guiding hand of linear level design - but then throws open the gates to the kingdom and lets you explore as you wish. And by letting you access so much content simultaneously, and by providing multiple routes and methods to get through the game, Hollow Knight almost never falls into the trap that Metroidvanias can find themselves in: of having you scour the map for that one single place you need to go, to make any progress.

Instead, Hollow Knight just lets you get on with exploring - with the promise that there will be something worth finding around every corner. A fascinating new zone, a bizarre one-off enemy, a chunk of cryptic world-building, a genuinely helpful item, a game-changing upgrade, or a terrifying boss monster. This is quite different to other Metroidvanias, mind you - it misses that puzzle-like aspect of slowly unravelling at a knot that binds the world together, one lock at a time.

But the feeling this game gives is perhaps even better - just pure, unadulterated wonder and immersion in a world that never stops surprising. Team Cherry told me that “we try to let the player loose in a wild world, not push them explicitly one way, and reward them for choosing their own path.” “That approach is based on mutual trust and respect between us and the player. We know these are smart, dedicated people and we’re confident that, through observation, tenacity and skill, they’ll deal with the challenges the world presents and ultimately gain mastery over it.

It’s that mastery, in exploration, in combat and in understanding the story of the world that we hope creates a memorable experience.” It certainly did for me, and to say I’m excited for the game’s sequel, Hollow Knight: Silksong, would be a massive understatement. And that is a wrap on Boss Keys. In the last 20 episodes I’ve looked at every major Zelda game, almost every Metroid game, Castlevania Symphony of the Night, Dark Souls, and now Hollow Knight.

The series is not gone forever, of course - I’ll be back when huge new games like Metroid Prime 4, Hollow Knight Silksong, and Breath of the Wild 2 are released. And yes, I do still plan to do that wrap-up episode on Zelda dungeon design. One day, promise. But I always planned for Hollow Knight to be the final destination for this series. It’s one of my favourite games and I think it might be the best Metroidvania ever made.

So it’s good to go out on such a high. Thank you so much for watching, and cheers to my Patrons for supporting this show. I’ll see you next mission.