The Book of Many Things

Chapter 2: Key

Deck of Many Things is a complex magic item, and introducing one to your game can be challenging. This chapter addresses numerous topics especially important to the Dungeon Master:

The origin and nature of the deck
Using a deck without disrupting your campaign (more than you want to)
Building a deck that contains only specific cards
Integrating a deck's effects into your campaign
How characters handle and use a deck in play
New magical effects associated with each card
Adventure seeds for characters who want to create their own cards

A Deck of Many Stories

The story of the Deck of Many Things began when a human woman named Asteria bargained with Istus, a god of fate, to save the life of Euryale, her dearest friend. As part of this bargain, Istus created a deck of twenty-two magical cards drawn from constellations in the night sky, and she used thirteen of these cards to change the destinies of Asteria and Euryale. These cards formed the first Deck of Many Things, an artifact with vast and unpredictable powers (the deck's origin is explored further in chapter 22).

Thanks to the deck's divine origin and unusual nature, it soon manifested in myriad lesser forms throughout the multiverse. Some of these wondrous items had fewer cards—typically only the thirteen cards used in Istus's reading for Asteria. Occasionally a deck manifested as something else entirely: a circle of twenty-two doorways, or a die with twenty-two sides, each roll of which had the power to change an individual's destiny.

Soon those inspired by the deck sought to create their own magical cards. Most of these efforts resulted in entirely new magic items, such as the Deck of Miscellany (see chapter 6) or the Deck of Wonder (see chapter 7). But occasionally, a legendary mage or a priest dedicated to the gods of fate and destiny succeeded in creating a new card that appeared alongside the Deck of Many Things, and that card replicated throughout the multiverse; these new cards make up the Deck of Many More Things, detailed in chapter 7.

Decks of Many Things have claimed many lives. Those who draw the Skull must fight an avatar of death, and those slain by this avatar rise again as Undead, doomed to exist as long as the decks do. Over the centuries, these Undead gathered to form the Grim Harrow, a horde of merciless hunters traveling the multiverse on a quest to find and destroy every manifestation of the deck so they can end their doomed existence (see chapter 19 for more on these beings). To combat these dangers, an angel founded the Solar Bastion (see chapter 10), a benevolent organization dedicated to protecting innocent people from the decks and the many dangers they pose.

The Grim Harrow and the Solar Bastion have learned much about the original deck over the centuries, but no one knows more about it than Asteria herself, who still travels the multiverse living out the destiny foretold for her by Istus long ago.

But in your campaign, the deck might have a different story. Perhaps the Deck of Many Things already existed when Istus used it to read Asteria's future, and it has another origin entirely. Perhaps it was the creation of a powerful faerie trickster or made by gods of chance as a test for greedy mortals. Use the story that best suits your campaign.

[image: Istus creates the first Deck of Many Things]

Preparing to Use the Deck

The power and unpredictability of a Deck of Many Things gives it the potential to wildly alter the course of campaigns. In an instant, characters could inherit a keep, shifting the campaign's focus to its defense and maintenance; a character could become separated from the rest of the party, trapped in an undetectable and unreachable prison; or characters could instantly perish. While some groups embrace such surprising twists, others prefer to avoid major campaign upsets.

This book provides tools to help you use the deck on your own terms. The following sections detail two ways to head off potential complications before the characters draw their first card. "Customizing Your Deck" suggests strategies for stacking the deck with only cards that will be fun for your group. Meanwhile, "The Deck as Narrative" discusses having cards foreshadow future events, rather than triggering instantaneous effects, so you can incorporate the effects into your campaign when the time is right.

The rest of this book also contains a wealth of advice and tools that address the challenges posed by specific cards. For example, the keep described in chapter 15 is perfect for any character who draws the Throne card. The three powerful fiends found in chapter 20 make ideal enemies for those who draw the Flames card. Chapter 18 includes a full map of the Void's prison, as well as suggestions for working with players whose characters are imprisoned there. With these resources in hand, you'll be free to enjoy where the cards lead your characters.

Customizing Your Deck

The easiest way to ensure the Deck of Many Things doesn't radically alter your campaign is to limit the cards you include, selecting cards appropriate for the characters' level or that support the campaign's theme. The number and effects of the cards provided in the Dungeon Master's Guide are suggestions you can change as necessary. The deck has had many variations over D&D's history, so when you change it, you're in good company!

Here are examples of customized decks that reinforce a campaign's tone, appeal to particular kinds of players, or avoid specific dangers:

Starter Deck. This version of the Deck of Many Things is meant for low-level characters, potentially as low as 1st level: Comet, Fates, Fool, Key, Knight, Rogue, Ruin, Sage, Talons.
Roleplaying Focus. Players who enjoy intense roleplaying and interacting with nonplayer characters will get the most from this deck: Balance, Fates, Flames, Knight, Rogue, Ruin, Sage, Throne.
Lighthearted. Most of the cards in this deck bestow benefits on those who draw them, and the few exceptions are relatively easily recovered from: Comet, Fates, Fool, Gem, Jester, Key, Knight, Moon, Ruin, Sage, Star, Sun, Throne.
Deck of Horrors. In this deck, perhaps found in Ravenloft or similar settings, harmful cards far outnumber helpful ones: Balance, Comet, Donjon, Euryale, Flames, Fool, Jester, Puzzle, Rogue, Ruin, Skull, Talons, Void.

You can supplement these decks with cards from the Deck of Many More Things, detailed in chapter 7.

The Deck as Narrative

Traditionally, the effects created by the Deck of Many Things are immediate. When a character draws the Knight card, a fighter immediately appears and offers their service, and a character who draws the Gem card might be literally showered with riches. While this suits some campaigns, you can take a more narrative approach to the deck by having cards foreshadow future events that occur at a time of your choosing. When you use the deck in this way, drawing from it is less like pulling the lever on a cosmic slot machine and more like allowing a character to select a new story for themself without being allowed to know that story ahead of time.

With this narrative approach to the Deck of Many Things, you decide how to weave the events triggered by cards into your campaign. For example, a character who draws the Knight card might meet a warrior along the side of the road, in a tavern, or even trapped in a dangerous dungeon; by freeing the warrior, the character earns the warrior's loyalty. A character who draws the Gem card might find a rich store of jewels in their next treasure hoard, or they might inherit great wealth when a relative dies. Many of the chapters in this book include advice to help you work the effects of their cards into your campaign story.

Using the deck's effects as events in your campaign poses an interesting question: is the deck predicting those events or causing them? If a character draws the Flames card, and soon after, minions of Aurnozci (see chapter 20) try to capture them, is this a direct result of drawing the card, or would the demons have attacked them anyway? The Book of Many Things doesn't answer this question; the answer is up to you and your players.

When you take a narrative approach to the Deck of Many Things, don't put off card effects for too long. It's okay for players to wonder for a session or two exactly when and how the effects will manifest, and you can use that time to devise clever and memorable ways to interpret the effects and keep the players in suspense. For example, a beloved ally might come to hate a character who draws the Rogue card, and that ally might conceal their hatred for several sessions before revealing it in a moment of sudden treachery. But new stories soon crowd out the old, and players might not be impressed if a card takes too long to manifest.

Introducing the Deck

This book provides several ways to introduce the Deck of Many Things to your campaign, depending on the interests of your players and the kind of story you want to tell.

The mysterious faerie market described in chapter 14 is home to a nilbog fortune teller named Oddlewin who uses a Deck of Many Things to read the future of his customers. This might be the first time that characters see the deck, and if they're willing to perform a service for Oddlewin, he might let them draw from it. This is a good way to introduce the deck to low-level characters.

Heroes of a more adventurous bent might explore the ruins of Gardmore Abbey presented in chapter 16. The abbey has long been associated with the deck, since an ill-fated draw caused a massacre of both the knights who defended the site and the army that besieged them. Now the ruins are home to Mekkalath, a red dragon, and a Deck of Many Things lies in his hoard. Few adventurers are powerful enough to challenge Mekkalath directly, but where might is insufficient, guile and cunning can prevail.

Finally, the characters might simply be given a deck by someone who wants them to have it. Rifflers, mischievous fey presented in chapter 21, are obsessed with the decks and constantly move them through the multiverse in a vain effort to manipulate destiny and complete a master plan only they understand. Alternatively, Asteria or Euryale, detailed in chapter 22, might give a deck to characters desperate to change their destiny.

Hello there! I've snuck some notes throughout this book—it felt appropriate, given my experience with this wondrous deck. May my words provide you with insight and inspiration!
— Asteria

The Deck in Play

This section clarifies many things about how individuals can use and handle a Deck of Many Things without triggering its fantastic powers. New magical abilities for each card are also provided, allowing characters who find only a few cards to engage with this magic item in their adventures.

You'll also find guidelines for characters who want to create new cards for the deck's complement, the Deck of Many More Things.

Handling the Cards

The Deck of Many Things has the power to transform anyone who draws from it, but to trigger its effects, the individual handling the cards must state their desire to draw from it, as well as the number of cards they intend to draw. Otherwise, the deck's magical powers lie dormant. Anyone who identifies a deck learns this about the deck in the process, per the rules for identifying magic items.

This means that under normal circumstances, characters can handle a Deck of Many Things safely. A character who finds a deck can look at it, spread the cards out, and otherwise manipulate the cards without triggering their effects. This is why folk are able to use decks as divinatory tools, placing cards before themselves to gain insight into the future or personal dilemmas without triggering the cards' effects.

But accidents do happen. A curious stranger who spots a deck, face down, might reach out to draw the topmost card without realizing the import of their actions, spurring an adventure that draws the characters' attention. While the decks aren't sapient and have no thoughts or goals of their own, many people report feeling a compulsion to draw from decks whenever they are near.

Effects for Single Cards

A Deck of Many Things typically appears not as individual cards, but as a collection of cards characters can draw from. But this doesn't have to be true; you can give each card a property as a standalone item, so characters who find only one card can still enjoy this famed item and use the card on adventures.

[image: The deck has replicated throughout the multiverse in infinite combinations]

This approach is particularly useful if you make a Deck of Many Things the object of a quest; as the characters explore, each card they find grants them a magical ability they can use in subsequent adventures to find the cards that remain. Eventually the heroes assemble the entire deck, which they can then use in the traditional manner, drawing transformative cards from it in a fitting climax to the campaign.

You can grant the following additional magical properties to the cards of the Deck of Many Things:

Balance. As an action, you can brandish this card at one creature you can see within 30 feet of yourself and drain its life force. The target must succeed on a DC 17 Constitution saving throw or take 4d8 necrotic damage. You then regain a number of hit points equal to the necrotic damage the target takes. Once this property is used, it can't be used again until the next dawn.
Comet. As an action, you can hold this card aloft and call down a fiery meteor to a point you can see within 120 feet of yourself. Each creature within a 20-foot-radius sphere centered on that point must make a DC 17 Dexterity saving throw. On a failed save, a creature takes 6d6 bludgeoning damage and 6d6 fire damage, or half as much damage on a successful save. Once this property is used, it can't be used again until the next dawn.
Donjon. As an action, you can brandish this card at one creature you can see within 30 feet of yourself. The target must succeed on a DC 17 Charisma saving throw, or it vanishes, transported to a prison on another plane of existence. After 1 minute, the target reappears in the space it left or in the nearest unoccupied space if that space is occupied. Once this property is used, it can't be used again until the next dawn.
Euryale. As an action, you can brandish this card at one creature you can see within 30 feet of yourself and attempt to turn it to stone. The target must succeed on a DC 17 Constitution saving throw, or it begins to turn to stone and has the restrained condition. The affected target must repeat the saving throw at the end of its next turn. On a successful save, the effect ends on the target. On a failed save, the target has the petrified condition (instead of the restrained condition) until it is removed by the Greater Restoration spell or similar magic. Once this property is used, it can't be used again until the next dawn.
Fates. As a bonus action, you can brandish this card at one willing creature you can see within 30 feet of yourself, granting the creature a brief glimpse of the future. Until the start of your next turn, the creature has advantage on attack rolls, ability checks, and saving throws. Additionally, other creatures have disadvantage on attack rolls against the target for the duration. Once this property is used, it can't be used again until the next dawn.
Flames. You can use this card to summon a devil. The card is attuned to a specific devil with a challenge rating of 8 or lower. As an action, you can hold this card aloft and summon that devil, which appears in an unoccupied space you can see within 30 feet of you. The devil is initially unfriendly toward you and your companions. Roll initiative for the devil, which has its own turns. The DM has the creature's stat block. On each of your turns, you can issue a verbal command to the devil (no action required by you), and as long as you are holding this card, the devil obeys your commands. Otherwise, it is under the DM's control and acts according to its nature—it might attack you if it thinks it can prevail or try to tempt you to undertake an evil act in exchange for further service. After 1 minute or when the devil's hit points drop to 0, the devil returns to the Lower Planes. Once this property is used, it can't be used again until the next dawn.
Fool. As an action, you can brandish this card at one creature you can see within 30 feet of yourself. The target must succeed on a DC 17 Wisdom saving throw, or for the next minute, the target can't cast spells or activate magic items, it has disadvantage on all saving throws, and other creatures have resistance to all damage it deals. Once this property is used, it can't be used again until the next dawn.
Gem. This card holds one 6th-level spell (chosen by the DM). As an action, you can brandish this card and use it to cast the spell stored inside (spell attack bonus +9, save DC 17). Once this property is used, it can't be used again until the next dawn.
Jester. As an action, you can brandish this card and use it to cast the Otto's Irresistible Dance spell (save DC 17), and you have advantage on Constitution saving throws to maintain concentration on it. Once this property is used, it can't be used again until the next dawn.
Key. As an action, you can brandish this card and use it to cast the Knock spell, with no sound made by the spell. This property can be used five times, and it regains all expended uses at dawn.
Knight. As an action, you can throw this card to an unoccupied space on the ground within 60 feet of yourself while speaking a command word, whereupon the card magically transforms into a deck defender (see chapter 9 for its stat block) for up to 1 minute or until you use an action to speak the command word again, whereupon it transforms back into a card. The deck defender obeys your spoken commands. If you issue no commands, it takes the Dodge action and moves to avoid danger. The deck defender reverts to a card early if it drops to 0 hit points. Once this property is used, it can't be used again until the next dawn.
Moon. As an action, you can speak a command word while touching this card and transform into a wolflike biped for 1 minute. For that duration, you have resistance to bludgeoning, piercing, and slashing damage, and when you hit a target with a weapon or an unarmed strike, the target takes an extra 1d6 force damage. Once this property is used, it can't be used again until the next dawn.
Puzzle. As an action, you can hold this card aloft and magically disable each trap within 60 feet of you that isn't behind total cover. A trap, for the purpose of this property, includes any object or mechanism that would inflict a sudden effect that was intended by its maker to cause harm or inconvenience. If the trap is the effect of a spell, such as Alarm, that trap is suppressed for 10 minutes instead of being disabled. Once this property is used, it can't be used again until the next dawn.
Rogue. When you hit a target with a weapon attack while holding this card, you can deal an extra 6d6 force damage to that target. Once this property is used, it can't be used again until the next dawn.
Ruin. As an action, you can brandish this card and use it to cast the Disintegrate spell (save DC 17). Once this property is used, it can't be used again until the next dawn.
Sage. As an action, you can brandish this card and use it to cast the Contact Other Plane spell. When you cast the spell in this way, your questions are answered by the mysterious figure depicted on the card. Once this property is used, it can't be used again until the next dawn.
Skull. As an action, you can brandish this card and use it to cast Spirit of Death (see chapter 7) as a 6th-level spell (spell attack bonus +9, save DC 17). Once this property is used, it can't be used again until the next dawn.
Star. As a bonus action, you can speak a command word while holding this card aloft to gain advantage on all saving throws you make for the next 10 minutes. Once this property is used, it can't be used again until the next dawn.
Sun. As an action, you can brandish this card and use it to cast the Sunbeam spell (save DC 17), projecting the light from the card's face. Once this property is used, it can't be used again until the next dawn.
Talons. As an action, you can brandish this card and target one magic item you can see within 120 feet of yourself. If the item isn't an artifact, its magical properties are suppressed for 1 minute. Once this property is used, it can't be used again until the next dawn.
Throne. As an action, you can speak a command word while holding this card to gain advantage on Charisma (Intimidation or Persuasion) checks for 1 minute. In addition, for that duration, you can use this card to cast the Command spell (save DC 17) as an action. Once this property is used, it can't be used again until the next dawn.
Void. As an action, you can brandish this card and attempt to banish up to three creatures you can see within 120 feet of yourself. If the target is from a different plane of existence than the plane you're on, the target must succeed on a DC 17 Charisma saving throw or be banished, returning to that other plane. Once this property is used, it can't be used again until the next dawn.

[image: The Knights of the Solar Bastion battle the Grim Harrow whenever the two groups meet]

Adding to the Deck

Over many centuries, a few dozen individuals have managed to create their own unique cards, expanding the deck. These cards, known as the Deck of Many More Things, can manifest throughout the multiverse alongside the twenty-two original cards, and the magical powers of the Deck of Many More Things are detailed in chapter 7. Characters can't craft a Deck of Many More Things, but in your game, they might be able to craft a new card for the Deck of Many More Things.

Anyone trying to make a card for the Deck of Many More Things must be at least 17th level. No formula for these cards exists, so the character must invent their own. While inventing the formula for such a potent magic item should take a long time, even years, a character can work on this project between or even on adventures. Characters might research their new formula by traveling to lost sites of ancient lore or locating others who have created cards of their own to learn how they accomplished this.

Once a character has invented the formula, they must acquire the magical ingredients—typically found only at great personal risk. Potential ingredients include magical inks made from crushed gemstones or the blood of legendary creatures, magical brushes or quills, and magical paper or other materials onto which the card must be painted (such as a dragon scale or a piece of the tarrasque's carapace). Great artistic skill is also required, so the creator might need to find a qualified artist or master the needed techniques themself. Furthermore, the magical ritual that creates the card must be performed at a specific time, perhaps when a particular constellation is in the sky. Divine intervention from a god of fate or destiny might be required.

While a character might be driven to create a new card as a matter of personal pride or a testament to the individual's magical prowess, consider rewarding a character who achieves this mighty goal with a benefit like one or more of the following:

Demiplane. Creating a card for the Deck of Many More Things simultaneously creates a demiplane inspired by the new card. The card's creator has complete control over this demiplane and can make it their permanent home.
Exclusive Membership. Card creators are powerful masters of magic who form a secret cabal. Once a year, they gather at a predetermined site to socialize, scheme, and decide the future of the multiverse.
Immortality. A character who adds a card to the Deck of Many More Things stops aging and can't die of old age until their card or the Deck of Many More Things to which it belongs is destroyed; then all their missing years suddenly catch up to them (probably killing them instantly).
World Walking. Adding a card to the deck allows the creator to travel to any world where their card has manifested as part of a Deck of Many More Things.

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