All Trident Key Locations and Puzzle Rewards in Queen’s Domain

There are five Trident Keys to collect in Queen’s Domain, but only two are necessary to progress through Obmuer Temple. The others are optional, although you’ll need all five if you want to uncover every secret and get the game’s fourth ending. Trident Keys are used to open locked doors throughout Obmuer Temple, access a hidden boss on the starting island, and solve a statue puzzle in the Petrified Garden.

Here’s where to find every Trident Key in Queen’s Domain, how to solve their associated puzzles, and the rewards you can obtain.

All Trident Key Locations in Queen’s Domain

Trident Key	Location	How to Obtain
Sapphire	Obmuer Temple	Found embedded in a wall in the first flooded cavern, beneath the ledge with an explorer’s note.
Emerald	Obmuer Temple	Found behind two skeletal archers next to the stairs right before the third Wind Gem.
Ruby	Outside Obmuer Temple	Obtain the Trident weapon and level it to 5 until its head breaks off.
Amethyst	Umbada’s Trading Outpost	Purchase for 15 Ancient Coins after giving Umbada the Golden Duck Figurine.
Onyx	Petrified Garden	Defeat Lost King Ojjama, the large whale-like boss found on the hidden island.

Trident Keys are reusable so you can remove them from locks after opening doors and insert them into different keyholes. This means you don’t need to collect all five keys to open the three-key door in Obmuer Temple. Sapphire, Emerald, and Ruby are enough.

Sapphire Trident Key Location

The Sapphire Trident Key is the first one you’ll encounter inside Obmuer Temple. From the first Crystal Monument, follow the path toward the explorer’s note beside a ledge overlooking a flooded cavern. Drop into the water below and defeat the Glaucusions swimming around the area.

Look along the wall near where you landed to find the Sapphire Key embedded in the stone wall.

There are two locked doors across the cavern. The door on the left requires one Trident Key, while the door on the right requires three. Insert Sapphire into the left-hand door to continue exploring the temple. Remember that you can return and retrieve it once you’ve opened the way forward.

Emerald Trident Key Location

The Emerald Trident Key is found deeper inside Obmuer Temple, near the third Wind Gem. After progressing beyond the first locked door, you’ll reach an enormous pit. Look down to find two openings in the wall and use Wind Dash to enter the accessible opening on the left.

Defeat the Toxic Homopiscium and other enemies in the lower area, then continue toward the staircase. You’ll encounter several Skeletal Soldiers and crossbowmen near the top. After clearing them, inspect the rocks nearby to find the Emerald Key.

This one blends into the surrounding environment, so it’s easy to miss if you rush through the enemy encounter.

Ruby Trident Key Location

The Ruby Trident Key is obtained by breaking the Trident weapon, which is found outside Obmuer Temple. The weapon is resting at the base of a statue beside the temple entrance, near the door that requires four Triangular Slates.

Pick up the Trident and equip it as your main weapon. Unlike most weapons, the Trident has a maximum weapon level of 5. Its description hints that the head isn’t properly attached, which is the clue to obtaining the key.

To break it:

1. Equip the Trident as your main weapon.
2. Attack enemies to increase its weapon experience.
3. Continue fighting until the weapon reaches Level 5.
4. The Trident’s head will break off, giving you the Ruby Trident Key.

The Trident is fairly useful for Obmuer temple since most enemies are weak to Pierce damage, so as long as you use it throughout the temple, you will eventually get the Ruby Trident Key.

Attacking walls or other objects won’t level the Trident, so you need to hit enemies. Note that once the weapon breaks, you won’t be able to use it anymore.

Amethyst Trident Key Location

The Amethyst Trident Key is purchased from Umbada’s Trading Outpost for 15 Ancient Coins. You’ll first need to defeat The Necronomicon in the Tower of Knowledge and obtain the Golden Duck Figurine. Give the figurine to Umbada to expand her inventory, then purchase the Amethyst Key.

Onyx Trident Key Location

The Onyx Trident Key is dropped by Lost King Ojjama, a whale-like boss found in the Petrified Garden hidden area. To access the Petrified Garden, begin teleporting between Wing Altars and step off the teleportation platform into the void while the travel animation is playing.

Once you arrive, explore the island and make your way toward the boss arena. Reaching the boss requires four Wind Dashes, although you can combine three Wind Dashes with the Cestus uppercut to cross the gap. Defeat Lost King Ojjama to obtain the Onyx Key. This is a very difficult boss fight and is meant for mid to late-game players.

All Trident Key Puzzle Locations and Rewards

The five keys are used for several puzzles throughout Queen’s Domain. Some open routes needed to progress through Obmuer Temple, while others lead to optional weapons, hidden bosses, and secret areas.

Puzzle Location	Keys Required	Reward/Unlock
Obmuer Temple, first flooded cavern	1	Opens the route deeper into Obmuer Temple.
Obmuer Temple, three-key gate	3	Engraved Halberd weapon.
Obmuer Temple, additional side doors	1–2	Optional rooms containing items such as Roasted Poultry, Meal Ticket, and the Silver Fish treasure.
Isle of Neasied, hidden passage near the well	5, split across two doors	White Tree Guardian boss and Mystical Nut of the White Tree.
Petrified Garden, central fountain	5	Awakens the garden, unlocks additional areas, and contributes to the route toward Ending 4.

How to Open the Three-Key Door in Obmuer Temple

The first major Trident Key puzzle is located in the flooded cavern where you obtained Sapphire. You’ll notice a three-key gate on the right side of the room. Behind it is a chest containing the Engraved Halberd, a weapon with 11 Power that deals both Pierce and Slash damage.

The easiest way to open this gate is with Sapphire, Emerald, and Ruby. After using Sapphire and Emerald to progress through the temple, return to their respective locks and retrieve them. Then insert all three keys into the gate beside the first flooded cavern.

Once all three are in place, the gate will open and you can collect the Engraved Halberd.

How to Access Locked Room With Hole in Obmeur Temple

As you progress through Obmuer Temple you’ll come across the second Rest point with Trident Key slots nearby. However, the middle room is inaccessible and you might assume that you need four Trident Keys to access it. Luckily, the solution is a lot simpler.

Once you beat the main boss of Obmeur Temple, you can take the left leading outside the temple. During the lift ride you can spot a hole in the wall and dash right in. Head inside and you can loot a Traveler’s Crystal and progress to the next room for a Roasted Poultry and a Silver Fish Treasure which can be sold for 20 Ancient Coins.

White Tree Guardian and Mystical Nut Trident Puzzle Location

There’s another Trident Key puzzle on the Isle of Neasied, the game’s starting island. Return to the area near the well, go through the shortcut on the left and you can find a hidden entrance concealed by bushes. The path is initially blocked, but you can press the interact key on the illusory wall to open it.

Inside, you’ll find a Meal Ticket and a locked door requiring three Trident Keys. Open it to access another chamber containing two additional keyholes. You’ll need all five keys to open both doors. Beyond the second door is the White Tree Guardian, an optional boss that drops the Mystical Nut of the White Tree.

The Mystical Nut is a Physical throwing weapon with 3 Power, a Very Slow return speed, and one available throw.

How to Solve the Petrified Garden Trident Key Statue Puzzle

The Petrified Garden has the most elaborate Trident Key puzzle in Queen’s Domain. After defeating Lost King Ojjama and obtaining Onyx, return to the central fountain area. You’ll notice five statues with Trident Key slots, each representing a different creature.

The solution involves matching each creature to the correct key color.

Statue	Trident Key	Color
Beetle / Ratty Bug	Amethyst	Purple
Slime	Sapphire	Blue
Bat	Emerald	Green
Stag / Deer	Onyx	Black
Fishman / Homopiscium	Ruby	Red

Once you’ve matched all five correctly, the Petrified Garden awakens, petrified enemies come to life, and previously inaccessible areas open. Completing the puzzle also unlocks the Living Stone achievement.

The keys may turn grey after the puzzle is completed, but you can still remove and reuse them.

Those are all the Trident Key locations, puzzles and their rewards in Queen’s Domain. Stick around for more in-depth guides.