If you’ve managed to make it through Act 3 of Inscryption and you’re looking for an extra challenge—or simply want to uncover every secret the game has to offer—then you’ll want to brace yourself for one of the toughest and most hidden boss fights in the game: the Mycologist’s Secret Boss.

This battle is not only mechanically intense but also dripping with eerie lore and ARG (alternate reality game) connections that feed into the unsettling mystery that Inscryption is known for. This guide will take you step-by-step through unlocking the boss, preparing for the encounter, and understanding its implications. Heads up: massive spoilers ahead.

Who Is the Mycologist?

The Mycologist is a recurring, off-kilter character introduced in Act 1 of Inscryption. Their gimmick is simple: when given two identical cards, they combine them into a singular powerhouse with stacked stats, but at the same cost. They show up across acts, always meddling with their strange fusion experiments—and in Act 3, they take center stage in one of the most hidden boss fights in the game.

How to Unlock the Boss

To face the Mycologist in Act 3, you first need to interact with them during Act 2. When you defeat one of the scribes, a familiar little hut appears on the right side of the map. Enter it, and the Mycologist will request specific card pairs to continue their experiments:

1. Gravedigger
2. Field Mice
3. Sentry Drone
4. Blue Mage

These cards aren’t random this time. You must acquire two copies of each. Thankfully, they can all be found in their respective regions’ card shops. With a bit of persistence—spamming the shop refresh—you’ll find them. Be warned, the Sentry Drone is a bit trickier to locate, found in the top-right region. If you prefer not to gamble with RNG packs, farming gold via the Practice Dummy in Magnificus’s tower (2nd floor) is a consistent method.

Once you’ve fulfilled all four requests, the Mycologist will give a cryptic monologue before dropping a purple-glowing key beside the table. That’s your ticket to the boss.

Finding the Hidden Boss in Act 3

Fast forward to Act 3. In Bottopia, head to Eastern Bottopia using the waypoint. From here, you’ll find a hidden diagonal arrow in the lower right corner of the screen. This leads you to a strange purple-hued zone—eerily similar to the Mycologist’s lab.

Use the purple key to unlock the door, and once you step in, the madness begins. The Mycologist seizes control of P03’s body, warping it into something grotesque. Thus begins the fight.

Phase One: The Fusion Frenzy

This is arguably the hardest part of the encounter. The Mycologist will continuously shift their cards toward the center column. Once two cards meet in the middle, they fuse—combining stats and sigils into monstrous “super cards.”

Your goal? Stop the fusion.

• Target and eliminate enemies before they reach the center.
• Prioritize direct damage over setup.
• Use removal tools wisely—these cards become nearly unstoppable once combined.

Failing to thin the herd early often results in the board being overrun by fusion monstrosities, which will crush your side in just a few turns.

Phase Two: Mirror, Mirror

Survive the fusion frenzy, and you’ll trigger the second phase. This time, the Mycologist fuses your cards on the board into a single amalgamation—on both sides. You’ll end up with a fusion card, and so will they.

Thankfully, this phase is often easier than the first:

• If you had a well-established board in Phase One, your amalgamation will likely be powerful.
• The Mycologist tends to have fewer resources by this point.
• All new cards played will slowly shift and fuse again—but the tempo favors you.

The fusion system here becomes your weapon instead of your threat.

Reward: The Microbot

Defeating the Mycologist doesn’t just bring a sense of closure—it also gives you a Microbot card. This card retains the final stats and sigils it had during the battle, offering a flexible, potent addition to your deck going forward.

Lore Implications and ARG Connection

This boss fight isn’t just mechanically unique—it’s narratively loaded. The Mycologist hints at experimenting with “old data”, the same forbidden material tied to the game’s ARG and the Bone Lord.

Their final act—fusing a mysterious card with what looks like a cryptic image—seems less about winning and more about reconstructing something ancient. Once done, they vanish, and P03 is restored with no memory of what happened.

The image left behind ties into Inscryption‘s larger ARG, a sprawling meta-narrative that reaches beyond the game’s borders. Fans eager to dig deeper will find this boss a key node in the unraveling mystery.

Final Notes

Facing the Mycologist is a high-risk, high-reward journey. It requires planning in Act 2, preparation in Act 3, and precise execution during the fight. But for players who crave the full Inscryption experience—both mechanical mastery and cryptic storytelling—this secret boss is unmissable.

Now that you know how to unlock and beat the Mycologist’s secret boss, it’s time to get fusing.

Good luck—and beware the center column.