How to Find the Grubs in the Ancient Basin in Hollow Knight

Learn how to find the Grubs in the Ancient Basin 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 encounters 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.

This guide will teach you how to find all the Grubs in the Ancient Basin!

Ancient Basin Grub 1

There are two Grubs in the Ancient Basin area. One can be found below a breakable floor near the top of the room near the middle part of Ancient Basin.

The Knight will encounter many enemies in the Ancient Basin, but the Knight will only encounter Lesser Mawleks on the way to the first Grub. 

Before the Knight can find the Grub that was mentioned, it is required that the Knight has the Mantis Claw ability, which allows the Knight to cling to walls and jump off of them, and the Desolate Dive Spell or the Descending Dark Spell (the upgrade of the Desolate Dive Spell), which allows the Knight to strike the ground with concentrated Soul and shadow. Finding the first Grub in the Ancient Basin will be no challenge with this spell and this ability.

To find the first Grub in the Ancient Basin, this is what the Knight must do:

1. From Deepnest or Kingdom’s Edge, enter the Tram and interact with the glowing button in the rightmost (or in the leftmost if you start from Kingdom’s Edge) part of the Tram to go to the Ancient Basin.
   
2. Next, exit the Tram, head to the left, jump across the exit below, continue to the left, drop down the gap after the metal platform’s edge, and then drop down the next exit below.
   
3. Then, head to the left, where the Knight will encounter a Lesser Mawlek, drop down the next path that leads downwards, then, upon landing, you will see that the floor is rumbling, which means that it is breakable.
   
4. Cast the Desolate Dive spell or the Descending Dark spell to break the floor, then at the bottom, head to the right where the Knight will encounter a Lesser Mawlek.
   
5. After defeating the Lesser Mawlek, continue to the right, and 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.

Ancient Basin Grub 2

The other Grub in the Ancient Basin can be found in the top left corner at the end of a maze on the western side near the middle of the Ancient Basin.

The Knight will encounter many enemies in the Ancient Basin. Still, the Knight will specifically encounter the following enemies on the way to the second Grub: Shadow Creepers and Infected Balloons.

Before the Knight can find the Grub that was mentioned, it is required that the Knight has the Crystal Heart ability, allowing the Knight to fly and dash continuously and horizontally until the Knight hits a wall, hits an enemy that was not killed by the hit, or if the player intentionally stops the dash, the Mantis Claw ability, allowing the Knight to cling to walls and jump off of them, the Mothwing Cloak ability, enabling the Knight to perform a horizontal dash forward, and the Monarch Wings ability, allowing the Knight to perform a secondary jump in mid-air. Finding the second Grub in Ancient Basin will be no challenge with these abilities.

Related: How to Find the Grubs in the Tower of Love in Hollow Knight

To find the second Grub in the Ancient Basin, this is what the Knight must do:

1. From the Bench inside the Tram in the Ancient Basin, exit the Tram, head to the left, and drop down the exit on the floor.
   
2. Then, drop down from the small platform, head to the left, jump across the gap towards the platform below on the left, continue heading to the left, and drop down the next shaft where the Knight will encounter a Shadow Creeper on the wall on the left, at the bottom the Knight will encounter another Shadow Creeper, head to the left, drop down the next gap, continue heading left upon landing, drop down the next shaft where the Knight will encounter another Shadow Creeper on the wall on the left, then take the exit on the right upon landing.
   
3. Next, head to the left and jump up the platform where there is a Bench. Sit on the Bench to heal the Knight and save your progress.
   
4. After that, head to the left, where there will be a big opening with spikes on the bottom and the ceiling; use the Crystal Heart ability to dash and fly to the right, and cancel the Crystal Heart ability by pressing the assigned JUMP button once the Knight is on the long platform near the end of the path so that the Knight will not hit the spikes on the wall, head to the left, jump up the platform above the spikes, then take the exit on the left.
   
5. Next, head to the left, jump up the next path upwards with the help of the Monarch Wings ability, then continue to head up the path and platforms with the help of the Monarch Wings ability.
   
6. At the top, head to the left, where the Knight will encounter a Shadow Creeper; head up the platforms on the left, where the Knight will encounter three Infected Balloons, then jump up the platform above on the right with the help of the Monarch Wings ability.
   
7. After that, the following must be done quickly: at the left edge of the platform, dash to the left with the help of the Mothwing Cloak ability, jump up the shaft with the help of the Monarch Wings ability, then climb up the shaft with the help of the Mantis Claw ability and head to the platform on the left.
   
8. Next, the following must also be done quickly: at the left edge of the platform, jump towards the left wall of the next shaft and slide down on it with the help of the Mantis Claw ability, just after the Knight slides off the bottom of the wall quickly dash to the left with the help of the Mothwing Cloak ability, jump up the next shaft with the help of the Monarch Wings ability, then climb up the shaft with the help of the Mantis Claw ability and head to the platform on the left.
   
9. Upon landing on the platform, the Knight will encounter another Infected Balloon.
   
10. Finally, head slightly to the left, and the Knight has found a Grub trapped inside a glass jar!

After freeing the Grub by striking the glass jar with the Nail, the Knight can exit the area by dropping down the shaft, then head and dash to the right with the help of the Mothwing Cloak ability so that the Knight will not fall on the spikes below.

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