How to Find the Grubs in the Royal Waterways in Hollow Knight

Learn how to find the grubs in the Royal Waterways in Hollow Knight!

Team Cherry’s Metroidvania action-adventure game, Hollow Knight, follows the journey of a nameless warrior called the Knight as he travels through Hallownest, now a kingdom ruined by a supernatural disease. As the Knight journeys through Hallownest, he will encounter various characters that will help fully unravel the story in the game. Some of these characters are cute little creatures called Grubs.

Grubs are small green creatures trapped inside glass jars that the Knight will find throughout Hallownest. These Grubs were trapped by a Void creature named The Collector, who loves to collect dead and alive bugs all around Hallownest and preserve them in glass jars.

The Knight will know if a Grub is nearby as its high-pitched crying can be heard in its general direction. Then, once the Knight finds one, the Knight can free them by striking the glass jar with the Nail to break it. After the Knight frees a Grub, it will do a little high-pitched shout of joy and burrow into the ground to return to its colony with the Grubfather.

There are a total of 46 Grubs all over Hallownest, and there are a few rewards for freeing a specific number of Grubs:

• For the first four Grubs found, the Grubfather, found in the northwesternmost part of the Forgotten Crossroads, will reward the Knight with Geo (10 Geo for the first Grub, 20 Geo for the second, 30 Geo for the third, and 40 Geo for the fourth Grub found).
  
• After freeing the fifth Grub, the Grubfather will reward the Knight with a Mask Shard.
  
• After freeing the sixth to ninth Grubs, the Grubfather will reward the Knight with Geo (50 Geo for the sixth, 60 Geo for the seventh, 70 Geo for the eighth, and 80 Geo for the ninth Grub found).
  
• After freeing the tenth Grub, the Grubfather will reward the Knight the Grubsong Charm, which allows the Knight to gain Soul when taking damage.
  
• After freeing the 11th to 15th Grub, the Grubfather will reward the Knight with Geo (90 Geo for the 11th, 100 Geo for the 12th, 110 Geo for the 13th, 120 Geo for the 14th, and 130 Geo for the 15th Grub found).
  
• After freeing the 16th Grub, the Grubfather will reward the Knight with a Rancid Egg.
  
• After freeing the 17th to 22nd Grub, the Grubfather will reward the Knight with Geo (140 Geo for the 17th, 150 Geo for the 18th, 160 Geo for the 19th, 165 Geo for the 20th, 170 Geo for the 21st, and 180 Geo for the 22nd Grub found).
  
• After freeing half (23) of the total Grubs, the Grubfather will reward the Knight with a Hallownest Seal, and the Grubfriend Achievement will be unlocked.
  
• After freeing the 24th to 30th Grub, the Grubfather will reward the Knight with Geo (200 Geo for the 24th, 200 Geo for the 25th, 205 Geo for the 26th, 210 Geo for the 27th, 215 Geo for the 28th, 220 Geo for the 29th, and 220 Geo for the 30th Grub found).
  
• After freeing the 31st Grub, the Grubfather will reward the Knight with a Pale Ore.
  
• After freeing the 32nd to 37th Grub, the Grubfather will reward the Knight with Geo (230 Geo for the 32nd, 235 Geo for the 33rd, 240 Geo for the 34th, 245 Geo for the 35th, 250 Geo for the 36th, and 255 Geo for the 37th Grub found).
  
• After freeing the 38th Grub, the Grubfather will reward the Knight with a King’s Idol.
  
• After freeing the 39th to 45th Grub, the Grubfather will reward the Knight with Geo (260 Geo for the 39th, 265 Geo for the 40th, 270 Geo for the 41st, 280 Geo for the 42nd, 290 Geo for the 43rd, 295 Geo for the 44th, and 300 Geo for the 45th Grub found).
  
• After freeing all of the Grubs around Hallownest, the Grubfather will reward the Knight the Grubberfly’s Elegy Charm, which allows the Knight to fire projectiles when attacking using the Nail and when at full health, and the Metamorphosis Achievement is unlocked.

In this guide, you will learn how to find all the Grubs in the Royal Waterways!

Royal Waterways Grub 1

There are three Grubs in the Royal Waterways area. One can be found inside a hidden breakable wall on the left side near the middle of the Royal Waterways.

The Knight will encounter various enemies in Royal Waterways, but the Knight will specifically encounter the following enemies on the way to the first Grub: Pilflips and a Belfly.

Before the Knight can find the Grub that was mentioned, it is required that the Knight has the Mantis Claw ability, allowing the Knight to cling to walls and jump off of them. The Monarch Wings ability allows the Knight to perform a double jump in mid-air, or the Mothwing Cloak ability allows the Knight to perform a horizontal dash forward.

Additionally, even though not needed, it is also recommended that the Knight has Isma’s Tear ability, allowing the Knight to swim in pools of acid without taking any damage. With these abilities, finding the first Grub in Royal Waterways will be no challenge.

To find the first Grub in Royal Waterways, this is what the Knight must do (this is assuming that it is the Knight’s first time in the area):

1. From the Memorial to the Hollow Knight in the southern part of the City of Tears, head to the left and take the exit; continue to the left until you find a path that leads downwards, then take that exit.
   
2. The Knight is now in the Royal Waterways. Upon entering, head to the left, where the Knight will encounter two Pilflips; at the end of the path, head down the path that leads downwards, where the Knight will encounter another Pilflip, then take the exit on the left.
   
3. Next, head slightly to the left, drop down the gap, head slightly to the right, then drop down the gap. At the bottom, you will see that the ground will rumble, which means it is breakable. Cast the Desolate Dive or Descending Dark spell on the ground to break it and head to the bottom of the shaft, then take the exit below. 
   
4. The Knight will drop down to a crooked Bench. Sit down on the Bench to save your progress. After that, head up the shaft above with the help of the Mantis Claw ability and head back to the previous room.
   
5. Then, head up the shaft with the help of the Mantis Claw ability, take the next path on the left, and head to the left, where the Knight will encounter a Belfly at the end of the path.
   
6. Next, drop down the pool of acid below on the left with the help of Isma’s Tear ability, then jump and strike the wall on the right a few times to break the hidden breakable wall. If the Knight does not have the Isma’s Tear ability, the Knight can drop down while clinging to the wall on the right with the help of the Mantis Claw ability, then just keep jumping up while striking the breakable wall on the right until it breaks.
   
7. After that, finally, head inside the newly-opened part of the room, and there, the Knight will find a Grub inside a glass jar!

After freeing the Grub by striking the glass jar with the Nail, the Knight can exit the area with the help of the Mantis Claw ability.

Royal Waterways Grub 2

The second Grub in the Royal Waterways area can be found in the rightmost part of Isma’s Grove, a sub-area located in the easternmost part.

The Knight will encounter various enemies in Royal Waterways. Still, the Knight will specifically encounter the following enemies on the way to the second Grub: a Flukemon, Flukefeys, Pilflips, Hwurmps, and Winged Sentries.

Before the Knight can find the Grub that was mentioned, it is required that the Knight has defeated the Dung Defender (in the eastern part of the Royal Waterways), turned the switch just ahead of the Dung Defender’s arena to remove the obstruction that leads to Isma’s Grove, obtained the Mantis Claw ability, allowing the Knight to cling to walls and jump off of them, the Crystal Heart ability, allowing the Knight to dash and fly continuously forwards until the Knight hits a surface or an enemy or until the dash or fly is intentionally stopped, the Isma’s Tear ability, allowing the Knight to swim in pools of acid without taking any damage, and the Monarch Wings ability, allowing the Knight to perform a double jump in mid-air, or the Mothwing Cloak ability, which allows the Knight to perform a horizontal dash forward. Also, the Knight must purchase the Lumafly Lantern from Sly in Dirtmouth to light up very dark rooms. Finding the second Grub in Royal Waterways will be no challenge with these abilities.

To find the second Grub in the Royal Waterways, this is what the Knight must do:

1. Starting from the crooked Bench on the left side near the middle of the Royal Waterways, head to the path on the right; take the path above at the end of the path where the path will be divided between the path down, middle, and up, and head to the right where the Knight will encounter a Flukemon.
   
2. Next, drop down the next shaft that leads downwards, where the Knight will fall into a pool of acid (without taking any damage thanks to the Isma’s Tear ability) and encounter a Flukefey, head to the right, jump up the platform, drop down the gap on the right, continue on the right where the Knight will encounter two Pilflips, jump up the elevated platform, continue to the right, drop down the gap on the right, continue to the right, then take the next exit downwards.
   
3. Then, upon landing, head to the left, drop down the gap where the Knight will encounter another Pilflip, head to the left where the Knight will encounter another Pilflip, and drop down the next gap towards a small platform where the Knight will encounter a Flukefey.
   
4. After that, drop down towards another small platform below on the right where the Knight will encounter another Flukefey, drop down towards another small platform below on the right, jump towards the path on the right, head to the right where the Knight will encounter a Pilflip, and jump up the elevated platform where there will be pink crystals at the end of the platform.
   
5. Next, from the pink crystal, use the Crystal Heart ability to dash and fly to the right to exit the room, pass through a room filled with spikes, and hit a wall in the next room.
   
6. After hitting the wall, jump towards the wall below on the left, where there are more pink crystals, and slide down on it with the help of the Mantis Claw ability; on the pink crystals, use the Crystal Heart ability to dash and fly towards the next wall on the right, and climb up the wall with the help of the Mantis Claw ability.
   
7. Then, at the top, head to the right, jump towards the small platform on the right above a pool of acid where the Knight will encounter a Hwurmp, and jump towards the next small platform above on the right where the Knight will encounter another Hwurmp, jump up the platform above on the left, and jump towards the platform above on the right where there will be another Hwurmp nearby.
   
8. Next, head up the shaft using the wall on the right with the help of the Mantis Claw ability; at the top, head to the right, drop down the gap on the right, and then take the exit on the right.
   
9. After that, head to the right, head up the next shaft with the help of the Mantis Claw ability, head up the large platform above in the middle with the help of the Mantis Claw ability where the Knight will encounter a Winged Sentry, continue heading up the room through the wall on the left with the help of the Mantis Claw ability, then jump and use the Monarch Wings ability or the Mothwing Cloak ability to get to the platform on the right where the Knight will encounter another Winged Sentry.
   
10. Then, head to the right, jump across the gap, continue heading to the right, jump another gap, and continue to the right, where the Knight will find a pool of acid.
    
11. Next, drop down on the pool of acid with the help of Isma’s Tear ability, swim to the right under a narrow path, jump up the platform on the right, drop down the shaft on the right, then head to the next opening on the left.
    
12. Finally, the Knight will find a Grub inside a glass jar! The Knight can now strike the glass jar and free the Grub!

Royal Waterways Grub 3

The third Grub in the Royal Waterways can be found up a hidden path in the northeasternmost part of the Royal Waterways.

The Knight will encounter various enemies in Royal Waterways. Still, the Knight will specifically encounter the following enemies on the way to the third Grub: A Husk Hornhead, a Husk Dandy, a Gluttonous Husk, Vengeflies, Belflies, Booflies, Hivelings, and Hwurmps.

Before the Knight can find the Grub that was mentioned, it is required that the Knight has the Mantis Claw ability, allowing the Knight to cling to walls and jump off of them.

The Crystal Heart ability, allowing the Knight to dash and fly continuously forwards until the Knight hits a surface or an enemy or until the dash or fly is intentionally stopped, and the Monarch Wings ability, allowing the Knight to perform a double jump in mid-air, or the Mothwing Cloak ability, allowing the Knight to perform a horizontal dash forward.

Also, the Knight must purchase the Lumafly Lantern from Sly in Dirtmouth to light up very dark rooms. Additionally, even though not needed, it is also recommended that the Knight has Isma’s Tear ability, allowing the Knight to swim in pools of acid without taking any damage. Finding the third Grub in Royal Waterways will be no challenge with these abilities.

To find the third Grub in the Royal Waterways, this is what the Knight must do:

1. Starting from the Bench in the King’s Station Stagway Station, take the exit to the left; the Knight will be in a room where they will encounter a Husk Hornead, a Husk Dandy, and a Gluttonous Husk, drop to the bottom and take the exit on the right which will have another Stagway sign.
   
2. Upon entering, the Knight will see a broken Bench in half, a flooded Stagway Station, and two Vengeflies. Kill both Vengeflies and drop down on the water.
   
3. Next, keep swimming to the right, where the Knight will go through a hidden passageway.
   
4. Upon entering, you will immediately encounter a dive-bombing Belfly, so dodge or hide below an elevated platform to avoid being damaged.
   
5. Then, jump up the platform, head to the right, where the Knight will encounter two separate Belflies, and take the exit at the end of the path.
   
6. Upon entering, the Knight will be on the central cliff of Kingdom’s Edge! Head to the right, where the Knight will encounter a Boofly above, drop down on the gap on the right, and head down the room using the small platforms where the Knight will encounter four more Booflies (be careful not to fall into the pool of acid at the bottom), just before the pool of acid at the bottom head to the path on the left, then take the exit.
   
7. After that, head to the left, jump across the gap where the Knight will encounter two Hivelings, continue to the left where the Knight will encounter three more Hivelings above a pool of acid, jump across the pool of acid and towards the platform above on the left, continue to the left, jump across the gap towards the platform above on the left, then take the next exit that leads upwards.
   
8. Next, climb up the wall on the right with the help of the Mantis Claw ability, jump towards the platform at the top on the left, and jump up the elevated platform above on the left, where there are pink crystals.
   
9. Then, from this platform, use the Crystal Heart ability to dash and fly towards the left, stop the Crystal Heart ability when the Knight is near a Hwurmp by pressing the assigned JUMP button, then head up the path above the Hwurmp and climb up with the help of the Mantis Claw ability and where the Knight will encounter a couple more Hwurmps.
   
10. Finally, head to the path on the left, and the Knight will find a Grub inside a glass jar there! The Knight can now strike the glass jar and free the Grub!

After finding all three Grubs in the Royal Waterways, the Knight is one step closer to finding them all, receiving the Grubberfly’s Elegy Charm and unlocking the Metamorphosis Achievement!