Summary
Hollow Knighthas become one of the most celebrated games in modern gaming. A landmark Metroidvania, it is recognized as a classic of the genre. Its lifespan extends even further with world-record speed runs and mods that take the gameplay to a whole new level.
Hollow Knightis renowned for its fantastic level design, unique visual style,and rewarding difficulty. At the core of its gameplay are the boss fights. There are47 bossesin total, ranging from the very simple to the downright grueling. Each has a unique set of moves and attacks that players will need to learn to achieve victory. With the addition of the Godmaster DLC, these bosses have even tougher variations to face off against.
Updated by Andy Chapman on July 12, 2025: Hollow Knight remains a popular Metroidvania, with new fans discovering the game every month. The game has become the standard for all modern Metroidvanias and is now considered a genre classic. Its stunning blend of fluid combat and immersive level design ensures players regularly return to take on the many challenges of Hallownest. This update has expanded the list of hardest Hollow Knight bosses by another four entries, including the iconic Mantis Lords and the charming Dung Defender.
24Flukemarm
A Fun Optional Boss
Deep within the dark, dank depths of the Royal Waterways, players will find the giant Flukemarm. This hidden boss can be a tough enemy as it constantly spews fast-moving Flukefeys, which can be tricky to deal with when trying to attack the large boss.
When entering into the arena, Flukemarm does not attack and only becomes hostile once the player initiates the fight. Players will find this hidden boss close to the main Royal Waterways bench. The Desolate Dive ability is required for a breakable floor, which gives access to the area.
23Brooding Mawlek
Big AOE Attacks
TheBrooding Mawlekis a hidden boss that can be accessed after the player receives the Mantis Claw. The boss is fought in a small room and has a large AOE attack that is tough to avoid. In addition to the spitting attacks are leaps and slashes that make maneuvering difficult.
An additional Brooding Mawlek is encountered during the grueling Trial of the Fool, where the player takes on different waves of enemies. The Brooding Mawlek can quickly trap the player underneath its spitting attack, causing a lot of damage. This boss fight is all about switching from each side of the room, learning the ideal time to switch and attack.
22Uumuu
Tough Platforming Boss Challenge
Uumuuis a large electric jellyfish-type creature that guards one of the three Dreamers, all of which are needed to completeHollow Knight’sstory. The difficulty of this boss isn’t in its speed or its devastating attacks, but in the tricky platforming challenge it poses.
Players can only dodge its various attacks for much of the fight, as Uumuu is immune to all damage until the NPC Quirrel appears to help the Knight. The boss summons electrical bursts that follow the player around, so constant movement is required. Players must react quickly to this fight, dealing as much damage as possible when Uumuu is open to attack. Players can reach the Teacher’s Archive through Fog Canyon, but will require the Shade Cloak beforehand. It is also recommended to acquire Irma’s Tear before taking on Uumuu.
21The Collector
Summons Multiple Enemies To Fight
The Collector is an optional boss found in the Tower of Love, accessed through Kingdom’s Edge. Many new players may miss this boss, as the key to the area is on the other side of the map, in the Queen’s Garden. Additionally, this key is only found if players have Isma’s Tear.
The Collector is a strange, shadowy enemy that kidnaps the many creatures of Hallownest in large jars. During the fight, he will release these enemies to attack the player. While The Collector is relatively straightforward, his nimble attacks and unpredictable movement can make him tricky to hit. Meanwhile, the increasing number of enemies released into the room can easily overwhelm players.
20Enraged Guardian
Precise Attacks That Deal High-Damage
The Enraged Guardian is the second phase of the Crystal Guardian boss fight players encounter earlier in the level. This version of the boss is faster and deals two masks of damage with each hit.
Players will find the boss located above the Crystal Guardian boss room. However, accessing the area requires the Monarch Wings ability. While most players will have little issue defeating the Enraged Guardian, his high-damage attacks come thick and fast. Like the previous fight with the Crystal Guardian, the Enraged Guardian requires good timing and careful positioning to defeat.
19Dung Defender
A Memorable Mid-Game Encounter
Found at the end of the Royal Waterways area, The Dung Defender is a fun battle that requires good timing and reactions. Like many battles inHollow Knight, the key to Dung Defender is memorizing the attack patterns and dealing damage at the correct moment. The fight is almost like a dance, as the Dung Defender dives across the arena throwing balls of dung at the player.
While the Dung Defender can take a few attempts to defeat, there are a number of tougher enemies in the game. Defeating this boss will grant access to Isma’s Grove, where players will find Isma’s Tear, an item that allows the player to swim in acid.
18Mantis Lords
An Early Challenge For New Players
One of the toughest challenges in the early game of Hollow Knight is the Mantis Lords boss fight. Located at the end of the Mantis Village, players challenge these three bosses in a fast-paced battle that requires strong reactions and precise movement.
Players first take on a single Mantis Lord, learning the movements and attacks. However, in phase two, the first Mantis Lord retreats, and players must take on the remaining two Lords at once. This battle is a test of players’ skills and is a formidable obstacle. Once defeated, players are free to explore Mantis Village without being attacked.
17Lost Kin
Fast Attacks & Spawns More Enemies
Lost Kinis a hidden dream boss found in the Ancient Basin area of the game. This encounter is a harder version of the Broken Vessel boss fight that players must defeat before taking on Lost Kin.
Like many of the fights inHollow Knight, the key to Lost Kin is in the timing. Learning the signs of each attack and reacting fast enough. As the fight progresses, smaller enemies will spawn continuously, making it difficultto stay calmand focused as the pressure increases. Lost Kin is a tricky battle, but one that will improve the player for tough fights later on.
16Failed Champion
High Damage & Falling Rocks
Failed Championis another of the hidden dream bosses inHollow Knightand can only be fought after defeating False Knight and acquiring the Dream Nail. Found in the Forgotten Crossroads, behind a hidden wall in the False Knight’s arena, this boss is a much harder encounter than the first time around.
Failed Champion has a higher aggression than False Knight, and each attack causes more damage. Like with False Knight, there are clearmoments that allow healingand shouldn’t cause too much trouble for players at this point in the game.
15Nosk
A Fast And Deadly Mimic Waiting In The Dark
Players looking to fully upgrade the Knight’s weapon must take on one ofHollow Knight’screepiest bosses.Noskis an infected shapeshifting monster that hunts the Deepnest region. Once players find the hidden wall that leads to the boss room, they will find another identical Knight haunting their way. Once approached, it will transform into Nosk and immediately attack the player.
Nosk is a tough fight, as it is fast, aggressive, and fires infected blobs at the player. There is very little space to avoid the large enemy, so timing is important in this battle. The boss room is filled with Nosk’s prey, which hangs from the ceiling, and it makes for one of the most memorable fights in the game. The entire region of Deepnest is the closestHollow Knightcomes to a horror game, and this fight is the perfect ending to the area.
