Where are all the secret bosses in Mina the Hollower?
Mina the Hollower hides nine optional bosses across its interconnected world, and most players will stumble into maybe two or three of them by accident. The rest are locked behind side quests, item collections, and some genuinely clever environmental puzzles. Miss them and you're leaving some of the best trinkets and upgrades in the game on the table. This guide covers every secret boss in order of when you're likely to encounter them, including exactly how to unlock each fight and what actually works in combat.
Midden's Ancestral Chamber arena
Midden (Queensbury: Ancestral Chamber)
Midden is the first secret boss most players will find. He's sitting behind a locked door in the Ancestral Chamber of Queensbury Crypt, and opening that door costs two Plasma Vials. Once inside, talk to him twice, then insult him to trigger the fight.
His attack patterns are straightforward: he lunges across the arena and sends out a swarm of flies to cut off your movement. The flies are the real problem here. Clear them out first, keep your distance while he resets, and punish him when he closes the gap. The reward is the Fly Bait Trinket.
Maxi (Road back to Ossex from Queensbury Crypt)
This one ambushes you. After clearing Queensbury Crypt and heading back toward Ossex, take the right-side entrance into town and Maxi drops in uninvited. He uses a version of the Nightstar whip with extended range and adds axe throws into the mix, so staying above ground for long stretches is a bad idea.
Burrow constantly. His projectile attacks are much harder to deal with at ground level, and going underground neutralizes most of his pressure. Beat him and you'll pick up a Trinket Bag, which lets you equip multiple trinkets simultaneously. That alone makes this ambush worth the stress.
Armand (Ossex, beneath Legovich's shop)
To find Armand, try purchasing a second item from Legovich the blacksmith in Ossex. Instead of selling you anything, Legovich hands over a letter from his brother refusing to work. Dig through the hole in the top-right of the shop to drop into Armand's lair.
Armand has a large health pool and resists physical damage by default, which makes him a slog if you don't handle the room correctly. Two lava spots sit at the top of the arena. Dig a channel to route the lava toward him, and while he's standing in it, he takes full damage from your attacks instead of the heavily reduced amount he'd otherwise receive. The lava damages you too, so don't get cute with positioning. Dodge his four-legged dashes and hammer strikes, and keep re-routing the lava whenever the debuff drops.
Route lava to break Armand's resistance
Dugin (Southern Outskirts or Western Hills)
Dugin is the most luck-dependent fight in the game. Talk to the two children Ack and Dak on High Street in Ossex after returning from Queensbury Crypt, and they'll fill you in on the legend of Dugin. The boss spawns in one of two locations: the Southern Outskirts near the man sunbathing, or the area just before Backwaters in Western Hills.
Which location it appears in is randomized, so check both. You need to beat Dugin twice to officially complete the encounter and claim the Lace Glove Trinket.
Willis (Ossex: Music Hall, Bowery)
Willis takes the most legwork to reach of any secret boss, but the quest itself is genuinely fun. After beating the Nox Beast, descend through the shortcut, then head left through a waterfall and up to the exit in the top-left. You'll find a frog sitting in a bucket. Your job is to escort it through the level without losing it. If the frog falls, it reappears on the nearest shoreline.
Once you reach the large swamp area in Backwaters with the moving platforms, knock the frog north to reunite it with Gumbo, Stan, and Zach. This earns you the Tumbling Tutu. Talk to the frog again and pay 100 Bones to fund the band's trip to Ossex.
With that done, head to the Music Hall in Ossex's Bowery. Burrow under the patrons at the entrance to bypass the bouncer, then talk to the large pirate shark near the stage. The fight itself is a war of attrition: attack Willis until he's exhausted, then throw him into the crowd to deal damage. Repeat until he's done. The Pneumatic Armlet Trinket is your reward.
Dark Deluxy (Windy Generator)
To trigger this fight, you need two Spark Containers. Find the door with two Spark slots on the way back from the Windy Generator, slot them in, then escort Luxy the moth back through the Windy Generator. That triggers the Dark Deluxy boss fight.
She's fast and she releases spores that restrict your movement and can be repositioned around the arena. Slow weapons struggle here. Bring a weapon with a high attack speed so you can punish her between movement bursts. Predict her patterns rather than reacting to them, and you'll get through it. The reward is a Spark Container, which makes the prerequisite cost break even.
Dark Deluxy's arena-controlling spores
Mirren (Coltrane Peak: Frostbite Woods)
Mirren is a ghost sitting in an abandoned carriage in Frostbite Woods. From the Underlab at Coltrane Peak, head right under the ice to the next area. Dig under the ice and use the block with the floating skull above it to give the larger ice chunk time to reform. Get inside, talk to Mirren, and tell her you're there to help. She won't believe you.
Her most dangerous move is cloning herself and diving across the screen, and she also fires will-o'-wisps. When the clones appear, stop attacking and focus entirely on dodging and burrowing to the left or right edge of the arena. Fighting in the middle of the room works fine for most of the encounter. Defeat her and collect the Blinking Glass Trinket.
Evra the Undying (Courtyard, Ossex)
Evra is the hardest secret boss in the game and the one with the strictest gear requirements. Before attempting this fight, have the Drill Driver Sidearm equipped, Keri the Wisp from a Poppit shop, and the Brisk Brew. Head to the eastern part of the Courtyard, find the woman with the bone head, and use a combination of Burrow Jump, hover, and the Drill Driver to clear the gap. Use the pipe you find to open a shortcut back here.
Spend three Vials to open the gate on the right, then explore the mini-dungeon until you find Evra in a grave. Her primary attacks are a charge and firing skeletal minions from her mouth that either attack directly or self-destruct near you. Her undead mount delivers massive body blows.
Burrow constantly to dodge both the mount and the skeleton swarm. Thinning out the skeletons gives you more room to maneuver around the mount's charges, so clearing the small enemies is actually worth your time here, unlike in most fights. Defeat Evra to earn a Health Rose.
Thalassion (Fishing Hole, Backwaters)
Thalassion is the most time-intensive unlock in the game. You need to catch all 15 fish spread across every area using the fishing rod obtained from Irwin and Durwin in Backwaters, leaving one fish remaining in Backwaters itself. Return to their hangout with the Fishing Rod and Drill Driver equipped (a raft works as an alternative to the Drill Driver). Head right from Durwin and your fish collection, navigate to the southeast corner, and use the Fishing Rod on the slime above to climb the gap. Continue into the next area to find Thalassion.
The arena is small and the boss hits hard. Thalassion swims around the perimeter launching water projectiles, and the only real attack window is when he dives down and exposes his tail with the yellow orb on it. Play defensively, be conservative about how often you swing, and wait for those tail exposures. After beating him, talk to Irwin, then return to Durwin to complete the fish collection and receive the Gilded Rod upgrade.
Thalassion's tight water arena
All secret boss rewards at a glance
What's the best order to tackle the secret bosses?
Most of these fights are gated by progression anyway, so the order largely handles itself. That said, a few practical notes: Maxi ambushes you automatically after the first dungeon, so there's no avoiding him. Armand and Midden are both early-game fights worth clearing immediately since the Trinket Bag from Maxi changes how you build your character going forward.
Save Evra and Thalassion for last. Evra genuinely requires late-game gear and the Drill Driver Sidearm, and Thalassion demands you complete the entire fishing collection first. Rushing either fight underequipped is a reliable way to waste time.
For everything else the game has hidden away, the full Mina the Hollower strategy guides cover bosses, side quests, collectibles, and more.