Rescuing the trapped Grubs scattered across the vast world of Hallownest is one of the most rewarding side quests in Hollow Knight. These tiny green creatures are locked inside glass jars, waiting for the Knight to break their prisons and send them safely back home. Finding all 46 Grubs requires a combination of keen exploration, specialized movement abilities, and patience.
Understanding the Importance of Saving Grubs
Every time you free a Grub, it returns to the Grubfather's home located in the far left section of Forgotten Crossroads. Visiting the Grubfather after rescuing his children rewards you with substantial Geo, valuable Mask Shards, Charm Notches, and rare crafting materials. Collecting every single Grub is also essential for completing your journal and earning high completion percentages.
While early Grubs are easy to locate, many later ones are hidden behind breakable walls and secret passages. Paying attention to faint crying sounds often alerts you to a nearby captive before you can visually spot its jar. Developing a habit of checking your map carefully helps ensure no hidden corners are left unexplored.
Essential Abilities Required for Grub Hunting
Many Grubs are completely inaccessible during your initial visit to a region due to environmental barriers. Key movement skills like the Mantis Claw, Monarch Wings, and Crystal Heart are necessary to reach high ledges and cross dangerous gaps. Acid resistance from Isma's Tear and the Shadow Cloak also open up previously hazardous pathways.
Attempting to collect every Grub before acquiring these core upgrades often leads to unnecessary backtracking and frustration. It is generally best to focus on main progression until you have built up a full suite of traversal abilities. Once your mobility is fully unlocked, sweeping through older zones becomes significantly faster and more efficient.
Utilizing Maps and the Collector's Map Item
Mapmaker Cornifer provides the initial layout for each region, but player mapping pins help mark unreachable Grubs for later retrieval. Tracking down every hidden creature manually can still be a daunting task given Hallownest's sprawling layout. Fortunately, the game includes a dedicated late-game item designed to make completion much smoother.
Defeating the optional boss known as The Collector in the Tower of Love grants you the Collector's Map. This unique key item permanently reveals the exact locations of all unrescued Grubs directly on your world map. With these markers visible, cleaning up remaining captives across different biomes becomes a straightforward process.
Strategies for Difficult Grub Encounters
Not every jar you encounter contains a genuine Grub ready to be liberated. A few containers throughout Hallownest actually hold Mimics that attack the moment their glass casing breaks. Listening closely or using Dream Nail on jars can help you identify hostile tricksters before striking them.
Some legitimate Grubs are protected by intense combat gauntlets or tricky platforming hazards like spikes and sawblades. Equipping defensive charms like Hiveblood or Grubsong can provide safety nets during tough movement challenges. Taking time to clear surrounding hazards before breaking a jar ensures a safe path back to the nearest bench.