Exploration in the desolate yet beautiful kingdom of Hallownest often requires more than just combat prowess; it demands a keen eye for hidden paths and the right tools to unlock them. Among the most essential utility items are the Simple Keys. These cheaply manufactured objects are vital for accessing optional NPCs, late-game challenges, and major shortcuts. In the original Hollow Knight, there are exactly four Simple Keys scattered across the map, matching the four Simple Locks you will encounter. Because these keys are interchangeable, understanding where to find them and which locks to prioritize can significantly alter the rhythm of a playthrough.

Quick Reference for Simple Key Locations

For those in immediate need of a location, here is a concise breakdown of where all four Simple Keys are hidden:

  1. Sly’s Shop in Dirtmouth: Purchased for 950 Geo after rescuing him.
  2. City of Tears: Tucked in an alcove below the City Storerooms.
  3. Ancient Basin: Found inside a Mawlurk corpse in the western section.
  4. Colosseum of Fools: Dropped by the Pale Lurker in a secret area behind the arena.

Every key is consumed upon use, meaning once you turn it in a lock, that specific key vanishes from the inventory. However, since the total number of keys matches the total number of locks, no player can be permanently locked out of content.

Detailed Guide to Obtaining the First Simple Key from Sly

The most straightforward way to obtain a Simple Key is through commerce. Once Sly, the diminutive merchant found in the Forgotten Crossroads, returns to his shop in Dirtmouth, he offers a variety of goods that are essential for early-game progression.

Rescuing Sly from the Crossroads

Before the key becomes available, players must locate Sly. He is found in the southeastern part of the Forgotten Crossroads, near the area where the Gruz Mother boss resides. He is currently suffering from the infection, appearing dazed in a small hut. After interacting with him, he returns to the surface.

Investing the 950 Geo

Sly sells the Simple Key for 950 Geo. For a new player, this might seem like a steep price. In our testing of early-game routes, the most efficient way to gather this amount is to complete the first two trials in the Forgotten Crossroads or to farm the Husk Guards located near the entrance to the False Knight’s arena. These guards drop a substantial amount of Geo and are relatively easy to kite with basic nail strikes.

Purchasing this key early is often recommended if you find yourself dying frequently and losing your Shade, as one of the primary uses for a Simple Key involves recovering lost Geo and Soul.

Navigating the Heights of the City of Tears

The second Simple Key is hidden within the rainy corridors of the City of Tears. This location requires a bit more platforming precision and awareness of the environment.

Reaching the City Storerooms

To find this key, start from the City Storerooms Stag Station. Head down into the large, vertical room filled with Winged Sentries. This room is characterized by its multiple platforms and a Whispering Root that can be activated for Essence.

The Secret Alcove

Descending from the top of this room, stay toward the right side. There is a topmost alcove protected by a Winged Sentry. In our experience, the easiest way to handle this encounter is to use the Vengeful Spirit spell to clear the sentry from a distance before attempting the jump. The Simple Key sits as a glowing pickup item at the very back of this alcove.

This specific key is often the one players use to enter the Royal Waterways, as the entrance to that zone is located just a few screens away to the south.

Excavating the Ancient Basin Mawlurk Corpse

The third key is located in the Ancient Basin, a subterranean region beneath the Royal Waterways. This area is notoriously difficult due to the presence of Lesser Mawlurks and the spiky terrain.

Requirements for the Search

Accessing this key typically requires the Crystal Heart (Super Dash) ability. The key is located in the western part of the Ancient Basin, near the bottom of the loop that leads toward the path for the Monarch Wings.

Entering the Mawlurk

In this area, players will encounter a large, dead Mawlurk. Unlike the living versions that spit acidic globs, this one is a static piece of the environment. By walking into the mouth of the corpse, you will find the remains of a Royal Retainer holding a Simple Key.

During our playthroughs, we found that the spikes in this area are the primary threat. Equipping the Grubsong charm can provide a safety net of Soul if you take damage, allowing for frequent healing during the trek back to the nearest bench.

The Secret Hunt for the Pale Lurker

The final Simple Key was added in the Godmaster update and is arguably the most difficult to obtain. It is not found lying on the ground; it must be taken by force from a unique NPC known as the Pale Lurker.

Finding the Hidden Wall

The Pale Lurker hides behind the Colosseum of Fools in Kingdom's Edge. To reach her, go to the right side of the main arena building, outside the cage walls. There is a breakable wall hidden behind the scaffolding. Beyond this wall lies a secluded, trash-filled area where the Pale Lurker resides.

Combat and Chase Tactics

The Pale Lurker is not a traditional boss but a skirmisher. She will flee from the Knight, dropping spikes and firing projectiles. She is incredibly fast and can be frustrating to hit with a standard nail.

  • Pro-tip: Equip the Shaman Stone and the Flukenest or Shade Soul. Because she moves so quickly, using large-area-of-effect spells is much more effective than chasing her for a nail strike. Once she is defeated, she drops the fourth and final Simple Key.

Strategically Unlocking the Four Simple Locks

Having the keys is only half the battle. Knowing where to use them is crucial for a smooth journey through Hallownest. The four locks serve very different purposes.

1. Confessor Jiji’s Cave (Dirtmouth)

Located at the far right of Dirtmouth, beyond the graveyard, is a stone door with a simple lock. Unlocking this provides access to Confessor Jiji. In exchange for a Rancid Egg, Jiji will summon the Knight’s Shade from anywhere in the world to her cave.

  • Best For: Players who have died in a dangerous area (like the Deepnest or a boss room) and want to recover their Geo without risking a second death. In Steel Soul mode, Jiji is replaced by Steel Soul Jinn, who buys Rancid Eggs for Geo.

2. The Royal Waterways Entrance (City of Tears)

In the center of the City of Tears, near the fountain of the Hollow Knight, there is a manhole cover with a keyhole. This is the primary entrance to the Royal Waterways.

  • Best For: Mid-game progression. The Waterways lead to Isma’s Grove and the Dung Defender boss fight. Opening this is usually the highest priority for players looking to finish the main story.

3. The Pleasure House (City of Tears)

Located near the King's Station, this lock grants access to a high-rise building containing a hot spring, the NPC Millibelle the Banker (after she steals your money), and the ghost of the songstress Marissa.

  • Best For: Lore enthusiasts and those needing a convenient hot spring near the King's Station. It also provides a shortcut to the Resting Grounds via an elevator.

4. The Godseeker’s Cocoon (Junk Pit)

Hidden in the Junk Pit (accessible through the Royal Waterways) is a massive, chained cocoon. Using the final Simple Key here unlocks the Godseeker.

  • Best For: Endgame players. Using the Dream Nail on the Godseeker grants access to Godhome, where the Pantheons and the ultimate challenges of the game reside.

Distinguishing Other Keys in Hallownest

New players often confuse Simple Keys with other quest-specific keys. It is important to note that a Simple Key cannot open doors that require specialized keys.

The Shopkeeper’s Key

This is a unique item found in the Crystal Peak. It must be returned to Sly to unlock his advanced inventory, including the Elegant Key. It is not a Simple Key and cannot be used in simple locks.

The Elegant Key

Purchased from Sly after giving him the Shopkeeper’s Key, this specific item opens a single door in the Soul Sanctum. Inside, players can find the Shade Soul spell upgrade.

The Love Key

Found in the Queen's Gardens, this key is used exclusively to unlock the Tower of Love in the City of Tears, which houses the Collector boss. It has a distinct appearance and is not interchangeable with Simple Keys.

Troubleshooting Common Issues

Some players have reported issues where keys do not appear to spawn. In most cases, this is not a bug but a misunderstanding of the requirements.

  • Sly not selling the key: Ensure you have actually spoken to him in the Forgotten Crossroads. If he is still in the hut, he won't be in Dirtmouth to sell his wares.
  • Pale Lurker not appearing: The Pale Lurker only appears if the Godmaster DLC is active (which is included in all modern versions of the game). Ensure you have found the correct breakable wall in Kingdom's Edge.
  • Key missing from City of Tears: Check your inventory to see if you have already used it. The Royal Waterways lock is the most common place players spend their first City key without realizing it.

Summary of Key Utility

The Simple Keys of Hollow Knight represent the game's philosophy of non-linear exploration. Whether you choose to prioritize the convenience of Confessor Jiji, the progression of the Royal Waterways, or the challenge of Godhome, these keys are your gateway to the deeper secrets of Hallownest. By visiting Sly, scouring the City of Tears, braving the Ancient Basin, and hunting the Pale Lurker, you will ensure that no door remains shut on your path to the center of the infection.

Frequently Asked Questions

Can I buy more than one Simple Key from Sly?

No. Sly only sells one Simple Key. The other three must be found in the world through exploration and combat.

Does it matter which key I use on which door?

No. The four Simple Keys are identical in function. Any key can open any of the four simple locks.

What happens if I lose my key?

It is impossible to "lose" a key in the traditional sense. Once picked up, it remains in your inventory until used. If you die, the key stays with you; it does not drop with your Geo.

Is there a fifth Simple Key?

In the base game of Hollow Knight, there are only four. While the sequel, Silksong, is confirmed to feature Simple Keys, they are part of a different game world with different mechanics.

Should I unlock the Pleasure House early?

Generally, no. The Royal Waterways and Confessor Jiji offer much more immediate utility. The Pleasure House is best saved for when you have excess keys or need to track down Millibelle.