Full list of all 63 Hollow Knight achievements. It takes around 60-80 hours to unlock all of the achievements in the base game on Windows.
The base game contains 52 achievements, and there are 3 DLC packs containing 11 achievements.
Achieve 100% game completion and finish the game in under 20 hours
Achieve 100% game completion and finish the game in Steel Soul mode
Finish the game in Steel Soul mode
Allow the Nailsmith to find a new calling
Leave Zote to die
Complete the game in under 10 hours
Complete the game in under 5 hours
Receive the Hunter's Mark
Record all of Hallownest's creatures in the Hunter's Journal
Achieve 100% game completion and finish the game
Acquire all Charms and receive Salubra's blessing
Collect 2400 Essence and hear the Seer's final words
Acquire all Mask Shards
Acquire all Vessel Fragments
Complete the Trial of the Fool
Rescue all of the imprisoned grubs
Defeat the Collector
Defeat the Radiance and consume the light
Aid the Herald in moving on
Defeat the Hollow Knight with Hornet by your side
Slay the Nailsmith with the Pure Nail
Bring peace to the Grey Mourner
Remember the past and unite the Abyss
Collect 1800 Essence and awaken the Dream Nail
Defeat the Soul Tyrant
Defeat the Failed Champion
Complete the Trial of the Conqueror
Defeat the Hollow Knight and become the Vessel
Destroy Lurien the Watcher
Spend a final moment with Quirrel
Defeat the Traitor Lord
Open all of Hallownest's Stag Stations and discover the Stag Nest
Acquire a map of each area
Destroy Monomon the Teacher
Defeat the Dung Defender
Complete the Trial of the Warrior
Defeat Zote in the Colosseum of Fools
Defeat Hornet in Kingdom's Edge
Rescue half of the imprisoned grubs
Acquire half of Hallownest's Charms
Destroy Herrah the Beast
Collect 600 Essence
Defeat the Lost Kin
Defeat the Broken Vessel
Defeat the Mantis Lords
Acquire 3 Vessel Fragments
Acquire 4 Mask Shards
Defeat the Soul Master
Open half of Hallownest's Stag Stations
Defeat Hornet in Greenpath
Defeat the False Knight
Acquire your first Charm
Defeat White Defender
Defeat Grey Prince Zote
Banish the Grimm Troupe from Hallownest
Defeat the Nightmare King and complete the Ritual
Defeat Troupe Leader Grimm
Achieve 112% game completion and finish the game.
Ascend the Pantheon of Hallownest and take your place at its peak
Complete the Pantheon of the Knight
Complete the Pantheon of the Sage
Complete the Pantheon of the Painter
Complete the Pantheon of the Master