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Overview

Mysteries are a type of Card. They are the primary objective of the game; the Investigators win the game by solving Mysteries in order to quell the Ancient One's rising. For most Ancient Ones, investigators must solve 3 Mysteries before the Ancient One awakens in order to win. If the Ancient One awakens, the investigators will normally have to solve an additional final Mystery which is significantly harder in order to win the game.

Some Mysteries are specific to one space on the board, in which case a Mystery Token is used to indicate that the active Mystery is on a particular space.

Mysteries always resolve at the end of the Mythos phase, after which a new Mystery is drawn, or investigators win the game.

Mystery Types

There are many different kinds of Mysteries, but each of them fits roughly into one of the following categories:

Research Encounter

Each Ancient One will usually have a Mystery wherein the investigators need to solve Research Encounters in order to place Clues on the Mystery to solve it. These Research Encounters are specific to each Ancient One. When investigators have solved a sufficient amount of Research Encounters and placed the Clues gained from these encounters onto the Mystery card, the Mystery is solved at the end of the Mythos phase. This number is usually equal to the number of investigators (NoInvestigators), or half that number. Any fractions are rounded up.

Defeat Epic Monster

Another common type of Mystery is one wherein investigators need to slay a spawned Epic Monster. The toughness of these Monsters generally scales with the NoInvestigators. These "Mystery Monsters" also often have special requirements in order to damage them, such as the Hydra which requires the active investigator to possess the Sword of Y'ha Talla in order to damage it. These Monsters are generally very powerful and usually require the efforts of multiple investigators to take down.

Special Encounter

Ancient Ones may also have a set of Special Encounter cards; some Mysteries require the investigators to encounter and successfully resolve a certain number of these cards in order to be solved. Special Encounters are generally more difficult than their Research Encounter counterparts, but have a wider variety of tests so that not only Observation specialists will be the best to handle them.

Item Requirement

Some Mysteries require the investigators to acquire a specific item (usually an Artifact). For example, Yig's Mystery, "Crown of the Serpent", requires the investigators to retrieve the Serpent Crown Artifact, perform a Will test, spend Clues, and then discard Ally Assets in order to solve the Mystery. In order to make these Mysteries fair, the Mystery often allows investigators to acquire the specific item they need if they would acquire an item from the specific item's category (i.e. if you would gain an Artifact, you may choose to gain the Serpent Crown instead).

Eldritch Tokens

Mysteries may sometimes spawn a number of Eldritch Tokens on the board. As encounters, investigators are usually required to perform various tasks successfully in order to place the Eldritch tokens on the Mystery card. Similar to the Research Encounter Mystery type, these Mysteries will often require a number of Eldritch tokens equal to or half the NoInvestigators.

This type of encounter is the most varied. Some will require the discarding of items, while others may have the investigator Ambushed by Monsters. Typically, if the encounter is resolved successfully, the Eldritch token is discarded from the board. As with Research Encounters, any item that advances the mystery should not remove an Eldritch token from the board, but should use an unused token to mark the Mystery card.

Final Mysteries

When an Ancient One awakens, with the exception of Azathoth, investigators will need to solve a Final Mystery in addition to the regular Mysteries in order to win the game. These Final Mysteries will often involve either directly confronting the Ancient One as a Monster, or successfully resolving a certain number of Special Encounter cards. Unlike other Mysteries, the Final Mysteries are not normal cards; they are printed on the back of the Ancient One sheets in their top right corner.

Advancing the Mystery

Other than performing the task listed on the card, there are other ways to complete the Mystery. Some Assets like the Treasure Map, Tasks like Seek the Truth, or stages on an Adventure can "advance" the Mystery, making it easier to complete. How specifically the Mystery advances depends on the Mystery type.

If the Mystery is one that places Eldritch Tokens on a card or on the board, place an unused Eldritch Token on the Mystery. Do not remove any from the board.

If the Mystery requires spending Clues to place a Clue on a card, use an Eldritch Token to stand in for the Clue. If Clues are spent all at once to solve the Mystery, investigators will need to spend one less Clue in order to do so.

If the Mystery involves an Epic Monster, that Monster loses 2 Health. This health is placed on the Mystery card, so an Epic Monster like The Brood, which doesn't spawn immediately, still loses that 2 health once it appears. If there is more than one Epic Monster spawned, such as the Ancient Cthonian, than each of the monsters loses 1 Health.

Some extremely rare cards like the Promise of Power can completely solve a Mystery. If this happens, simply turn over the next Mystery at the end of the Mythos Phase. Remove the Epic Monster or any unused Eldritch Tokens when you do so.

List of Mysteries

Name Ancient One Set Type
Child of Abhoth.png Child of Abhoth Abhoth 05
Under the Pyramids
Epic Monster
Exploring the Caverns.png Exploring the Caverns Abhoth 05
Under the Pyramids
Special Encounter
Sealing the Caverns.png Sealing the Caverns Abhoth 05
Under the Pyramids
Research Encounter
Spawn of Uncleanliness.png Spawn of Uncleanliness Abhoth 05
Under the Pyramids
Eldritch Tokens
The Source of Filth and Disease.png The Source of Filth and Disease Abhoth 05
Under the Pyramids
Research Encounter
Touched by Abhoth.png Touched by Abhoth Abhoth 05
Under the Pyramids
Eldritch Tokens
Dread Countenance.png Dread Countenance Antediluvium 09
Masks of Nyarlathotep
Artifact, Misc.
Emerald Dreams.png Emerald Dreams Antediluvium 09
Masks of Nyarlathotep
Misc.
Sleeper Ascendant.png Sleeper Ascendant Antediluvium 09
Masks of Nyarlathotep
Misc.
The Order of Rising Stars.png The Order of Rising Stars Antediluvium 09
Masks of Nyarlathotep
Research Encounter
Through the Ages.png Through the Ages Antediluvium 09
Masks of Nyarlathotep
Mystic Ruins Encounter
Time Immemorial.png Time Immemorial Antediluvium 09
Masks of Nyarlathotep
Eldritch Tokens
Beasts from Beyond.png Beasts from Beyond Atlach-Nacha 07
The Dreamlands
Misc.
Caught in the Web.png Caught in the Web Atlach-Nacha 07
The Dreamlands
Misc.
Severing the Links.png Severing the Links Atlach-Nacha 07
The Dreamlands
Misc.
Shroud of the Spider-Mother.png Shroud of the Spider-Mother Atlach-Nacha 07
The Dreamlands
Research Encounter
Sleeper of N'kai.png Sleeper of N'kai Atlach-Nacha 07
The Dreamlands
Epic Monster
The Brood.png The Brood Atlach-Nacha 07
The Dreamlands
Artifact, Epic Monster
Occult Research.png Occult Research Azathoth 01Core Research Encounter
Omen of Devastation.png Omen of Devastation Azathoth 01Core Misc.
Seed of the Daemon Sultan.png Seed of the Daemon Sultan Azathoth 01Core Misc.
The Green Flame.png The Green Flame Azathoth 02
Forsaken Lore
Epic Monster
The True Name.png The True Name Azathoth 01Core Eldritch Tokens
Voice of Azathoth.png Voice of Azathoth Azathoth 02
Forsaken Lore
Item Requirement
Queen of the Deep Ones.png Queen of the Deep Ones Cthulhu 02
Forsaken Lore
Epic Monster
R'lyeh Risen.png R'lyeh Risen Cthulhu 01Core Special Encounter
The Deep Ones Attack!.png The Deep Ones Attack! Cthulhu 01Core Eldritch Tokens
The Stars Are Right!.png The Stars Are Right! Cthulhu 01Core Research Encounter
Threatening Seas.png Threatening Seas Cthulhu 02
Forsaken Lore
Eldritch Tokens
Watching the Stars.png Watching The Stars Cthulhu 01Core Epic Monster
An Alien Ritual.png An Alien Ritual Elder Things 03
Mountains of Madness
Misc.
An Expedition Compromised.png An Expedition Compromised Elder Things 03
Mountains of Madness
Misc.
At the Mountains of Madness.png At the Mountains of Madness Elder Things 03
Mountains of Madness
Eldritch Token
Binding the Dark God.png Binding the Dark God Elder Things 03
Mountains of Madness
Misc.
Discovery of an Ancient Civilization.png Discovery of an Ancient Civilization Elder Things 03
Mountains of Madness
Research Encounter
Invasion of the Elder Things.png Invasion of the Elder Things Elder Things 03
Mountains of Madness
Epic Monster, Item Requirement
Mysterious Disappearances.png Mysterious Disappearances Elder Things 03
Mountains of Madness
Special Encounter
The Dark God's Prison Crumbles.png The Dark God's Prison Crumbles Elder Things 03
Mountains of Madness
Misc.
Beneath an Alien Sky.png Beneath an Alien Sky Hastur 06
Signs of Carcosa
Misc.
Cities on the Lake.png Cities on the Lake Hastur 06
Signs of Carcosa
Special Encounter
Finding the Way.png Finding The Way Hastur 06
Signs of Carcosa
Research Encounter, Item Requirement, Misc.
He Who Is Not to be Named.png He Who Is Not to be Named Hastur 06
Signs of Carcosa
Research Encounter
Ravages of the Blight.png Ravages of the Blight Hastur 06
Signs of Carcosa
Misc.
Spawn of Hastur.png Spawn of Hastur Hastur 06
Signs of Carcosa
Epic Monster
The King in Yellow.png The King in Yellow Hastur 06
Signs of Carcosa
Special Encounter
The Yellow Sign.png The Yellow Sign Hastur 06
Signs of Carcosa
Eldritch Tokens, Research Encounter
Descending the Steps.png Descending the Steps Hypnos 07
The Dreamlands
Misc.
Dream Within a Dream.png Dream Within a Dream Hypnos 07
The Dreamlands
Special Encounter
Dreamwalker.png Dreamwalker Hypnos 07
The Dreamlands
Special Encounter
Master of Dreams.png Master of Dreams Hypnos 07
The Dreamlands
Research Encounter
The Hubris of Man.png The Hubris of Man Hypnos 07
The Dreamlands
Item Requirement
Visions of Hypnos.png Visions of Hypnos Hypnos 07
The Dreamlands
Misc.
A Spreading Storm.png A Spreading Storm Ithaqua 03
Mountains of Madness
Research Encoutner
Exploring Hyperborea.png Exploring Hyperborea Ithaqua 03
Mountains of Madness
Special Encounter
Growing Hunger.png Growing Hunger Ithaqua 03
Mountains of Madness
Eldritch Tokens
Hyperborean Aurora.png Hyperborean Aurora Ithaqua 03
Mountains of Madness
Item Requirement, Misc.
The Gnoph-Keh Attack!.png The Gnoph-Keh Attack! Ithaqua 03
Mountains of Madness
Research Encounter, Misc.
Supplying the North.png Supplying The North Ithaqua 03
Mountains of Madness
Item Requirement, Eldritch Tokens
Exploring Egypt.png Exploring Egypt Nephren-Ka 05
Under the Pyramids
Eldritch Tokens
Haunter of the Dark.png Haunter of the Dark Nephren-Ka 05
Under the Pyramids
Epic Monster
Stricken from History.png Stricken from History Nephren-Ka 05
Under the Pyramids
Research Encounter
The Beast.png The Beast Nephren-Ka 05
Under the Pyramids
Epic Monster
The Black Wind.png The Black Wind Nephren-Ka 05
Under the Pyramids
Special Encounter
Worshipers of a Forsaken Pharaoh.png Worshipers of a Forsaken Pharaoh Nephren-Ka 05
Under the Pyramids
Misc.
Brotherhood of the Dark Pharaoh.png Brotherhood of the Dark Pharaoh Nyarlathotep 09
Masks of Nyarlathotep
Adventure
Cult of the Bloody Tongue.png Cult of the Bloody Tongue Nyarlathotep 09
Masks of Nyarlathotep
Adventure
Cult of the Sand Bat.png Cult of the Sand Bat Nyarlathotep 09
Masks of Nyarlathotep
Adventure
Order of the Bloated Woman.png Order of the Bloated Woman Nyarlathotep 09
Masks of Nyarlathotep
Adventure
Blasphemy of the Black Goat.png Blasphemy of the Black Goat Shub-Niggurath 02
Forsaken Lore
Epic Monster
Hour of the Moon Lens.png Hour of the Moon Lens Shub-Niggurath 02
Forsaken Lore
Eldritch Tokens
Hunting the Thousand.png Hunting the Thousand Shub-Niggurath 01Core Misc.
Nature of the All-Mother.png Nature of the All-Mother Shub-Niggurath 01Core Research Encounter
Rituals in the Wild.png Rituals in the Wild Shub-Niggurath 01Core Eldritch Tokens
Spawn of the Black Goat.png Spawn of the Black Goat Shub-Niggurath 01Core Epic Monster
Bringer of Ruin.png Bringer of Ruin Shudde M'ell 08
Cities in Ruin
Research Encounter
Disaster Relief Effort.png Disaster Relief Effort Shudde M'ell 08
Cities in Ruin
Misc.
Exploring G'harne.png Exploring G'harne Shudde M'ell 08
Cities in Ruin
Special Encounter
Renewing the Seal.png Renewing the Seal Shudde M'ell 08
Cities in Ruin
Eldritch Tokens
The Burrowers Beneath.png The Burrowers Beneath Shudde M'ell 08
Cities in Ruin
Epic Monster
The Worldrender.png The Worldrender Shudde M'ell 08
Cities in Ruin
Epic Monster
Discovery of the Cosmic Alignment.png Discovery of the Cosmic Alignment Syzygy 04
Strange Remnants
Research Encounter
Fortifying the Barrier.png Fortifying the Barrier Syzygy 04
Strange Remnants
Special Encounter
Plea to the Court of Azathoth.png Plea to the Court of Azathoth Syzygy 04
Strange Remnants
Eldritch Tokens
Relics of the Ancient World.png Relics of the Ancient World Syzygy 04
Strange Remnants
Item Requirement
Shrouded in Mysticism.png Shrouded in Mysticism Syzygy 04
Strange Remnants
Misc.
Unearthly Piping.png Unearthly Piping Syzygy 04
Strange Remnants
Misc.
Crown of the Serpent.png Crown of the Serpent Yig 02
Forsaken Lore
Item Requirement
Descendants of Yig.png Descendants of Yig Yig 02
Forsaken Lore
Epic Monster
K'n-yan Unearthed.png K'n-yan Unearthed Yig 02
Forsaken Lore
Special Encounter
Migration of Serpents.png Migration of Serpents Yig 02
Forsaken Lore
Research Encounter
Rise of the Serpent People.png Rise of the Serpent People Yig 02
Forsaken Lore
Eldritch Tokens
The Winged Serpent.png The Winged Serpent Yig 02
Forsaken Lore
Epic Monster
Arcane Understanding.png Arcane Understanding Yog-Sothoth 01Core Misc.
Spawn of Yog-Sothoth.png Spawn of Yog-Sothoth Yog-Sothoth 01Core Epic Monster
The Beyond One.png The Beyond One Yog-Sothoth 01Core Research Encounter
The Stone Circles.png The Stone Circles Yog-Sothoth 02
Forsaken Lore
Eldritch Tokens
Void Between Worlds.png Void Between Worlds Yog-Sothoth 02
Forsaken Lore
Special Encounter
Where the Old Ones Broke Through.png Where the Old Ones Broke Through Yog-Sothoth 01Core Misc.
Reign of Filth Abhoth 05
Under the Pyramids
Final Mystery
Cosmic Entanglement Atlach-Nacha 07
The Dreamlands
Epic Monster, Final Mystery
A Dark God Elder Things 03
Mountains of Madness
Special Encounter, Final Mystery
The Third Act Hastur 06
Signs of Carcosa
Special Encounter, Final Mystery
Corona Borealis Hypnos 07
The Dreamlands
Special Encounter, Final Mystery
Endless Winter Ithaqua 03
Mountains of Madness
Epic Monster, Final Mystery
Tomb of Nephren-Ka Nephren-Ka 05
Under the Pyramids
Final Mystery
Sealing the Portal Syzygy 04
Strange Remnants
Final Mystery
Serpent's Nest Yig 02
Forsaken Lore
Final Mystery
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