Dungeon The Gathering Logo

What this is

Dungeon: The Generating is a tool to use Magic: The Gathering cards to generate a dungeon for your tabletop RPG game. It can be used with a random selection of cards or a constructed deck, either on the fly (for more chaos), or during game preparations.

A note on Systems

The rules here are based on systems that use Ascending Armor Class, Difficulty Class and Hit Dice. Namely, D20 systems like DnD, Dungeon Crawl Classics, Old School Essentials, and so on. It is possible they will work for other types of systems out there (please let me know if you try and find success!), but these are the ones it has been designed with in mind.

A note on Knowledge

This generator assumes that you have some basic knowledge of Magic: The Gathering and the different parts of a Magic card. This included the terms like CMC (Mana cost), power and toughness, and card type, as a base. You do not need to know how to play Magic, just the base parts of the cards themselves. If you are unfamiliar with MtG, but have some cards around and want to give this generator a try, this Anatomy of a Magic Card article might help you out.

1. Building your Dungeon Deck

Building you dungeon is entirely optional. You could just grab a handful of cards and embrace the chaos. However, since Magic is designed around themes and mechanical interplay it can be pretty interesting to develop a Dungeon Deck around a theme or colour. It helps with flavour and narrative for the dungeon as well. For example, your game might be approaching a largely aquatic environment which would be a great moment to make a blue merfolk deck. Further to this, some Magic keywords work better for translating into an RPG system, so being intentional with the inclusion of cards can make the process a little smoother. But please, embrace the chaos at will. Below are some introductory guidelines and inspirations for building your Dungeon Deck.

Ratios of Card Types.

The ratio of card types you include in your deck is very up to the flavour and style of dungeon you want to be able to make. Maybe you want something swarming with small baddies and as such might have almost all creature cards and maybe a few equipments. Or maybe you want to make the dungeon itself sentient, in which case your ratio will skew more towards artifacts, instants and sorceries, with the artifacts taking the place of your sentient creatures. As a starting deck though, a good ratio is 50 percent Creatures, 20 percent Artifacts, 30 percent mix Sorceries, Instants and Equipment. Always 0 lands, they have no power here.

Room and Dungeon Size.

Start with 5 cards per room and adjust for density of desired action. As there is a chance you will roll high during the room generation phase it is advisable to include a couple extra rooms worth of cards. A single shot adventure (or a single level of a dungeon) might be 4-6 rooms so starting with 40 cards is good. This is conveniently the average amount of cards in a standard magic deck, when you remove the lands, so you can easily convert a playable MtG deck into a dungeon deck.

Casting Cost of your Cards

Casting cost in MtG is indicative of power level of the card and as such we can use it as a loose reference for power of our dungeon. Generally, you want the casting cost of the cards in your deck to be within 2 levels of your player characters. Adding a couple higher level cards in can make some fun moments happen, but a deck full of 7 or 8 mana cards will demolish a group of level 1 adventurers. Including a legendary creature or two with a higher CMC than your deck average is a great way to have a dungeon boss though. For cards that have an equip cost, use this instead of their casting cost to determine their relative-to-character level (some 1 mana equipments have 10 mana equip costs and will be extremely powerful).

Use a commander deck for multi session mid level play - they will give you a theme, some major characters to adapt to NPCs and a good few mini bosses to scatter throughout the dungeon.

2. Building Your Dungeon

Once you have your dungeon deck assembled, it's time to make something with it. Because these processes are separate you can easily reuse the same deck to make multiple dungeons or multiples levels (could even get that sideboard into play). To get started you will need your Dungeon Deck, a six sided die and some kind of note taking tools. Gridded paper is great if you want you make a map of the dungeon as you go.

For each room, roll a d6 to determine how many cards to draw. Draw your cards for the room and interpret them through the card types and effects listed below.

If you draw no creatures for you room, consider the cards a part of the environment. Sorceries may become traps and artifacts, treasures.

The Dice Chain

The Dice chain is a mechanic popularized by Dungeon Crawl Classics and something that gets used a few times for translating our cards. Unlike DCC, we will be using the standard set of 8 polyhedral dice for out chain. When the text says "move up the chain" it means step one to the right along this line:

D4 > D6 > D8> D10> D12> D20

Creatures

Creature cards are the basis for your dungeon and will represent the monster, opponents, and NPCs within in. Whether a creature card represents something antagonistic towards your plays or not is entirely up to you. A room full of goblins don't need to attack the players on sight and instead may be trying to start a rebellion against the dungeons tyranical leader, farther in. As a base, creature card stats can be translated into monster stats as follows:

Card Casting Cost (CMC)

This represents the Hit Dice of the creature. In order to make the scaling interesting this is done by reading the coloured mana requirement (represented by the circles with icons in them) and the colourless mana requirements (number in a grey circle) separately. For the purpose of this generator all coloured mana is the same. For each coloured mana symbol move the creatures Hit Dice up the chain. For each colourless mana, add another Hit Dice. A creature can never have less than 1 Hit Dice or go lower than a D4. Examples:

3WW- creature rolls 4D6 for it's hit points. 1D4 to start from a singular W (white symbol), one step up the chain from the second W, and 3 extra dice from the three colourless.

2GGB - creatures rolls 3D8 for Hit Points. Single D4 for the B (black symbol), up the chain twice for the 2 G (green symbol), and 2 extra dice for the 2 colourless.

Power and Toughness

Power and Toughness will translate the base combat actions for the creature. The Armor Class of the creature will be 10 + toughness. The basic attack of the creature will be generated by reading the power two ways, one as the attack bonus and one as the damage dice. The attack bonus is a straight translations, 1 power is equal to a +1 attack bonus. For the Damage Dice, the number represents the placement on the Dice Chain, 1 = d4, 2 = d6, etc. Effects that change power and toughness will change these as well. Use the card art or flavour text to help inspire that nature of the attack.

Example: A creature with 3/1 power and toughness would have a base attack of + 3 with a damage die of D8 and an Armor Class of 11.

Abilities

Where it is not possible to do a direct translation (ie. All allies +1 toughness), consult the Keyword list below or use them as general guidelines and adapt to your system of choice. Activated abilities (things that have a cost on the card) can be used each turn as an action, but must be recharged to use a second time if they have a cost (outside of a tap effect). To recharge, roll a D10 at the beginning of you turn and roll over the abilities cost. Abilities that require a condition should be met as closely as possible as the system allows. Where the ability is something the PC may have a chance to resist, make the DC of the save equal to 10 + toughness.

Example: Catti-Brie

Catti-brie of Mithral Hall has a lot of abilities and would make a good Boss encounter, assuming she is in a deck with equipment for her to wear. The equipment Moonsilver Spear summons angels to the battle everytime Catti-brie attacks.

Catti-brie. AC 12. Spear +2 D6 dmg. HD 1D6 (4).
Moonsilvered: On attack summon a 4/4 Angel with flying and buff Catti +1/+1
Hurl:Remove all buffs from Catti and add as dmg to attack (+1 buff for +1 damage)

Catti-Brie with the Spear is interesting. Her Casting Cost places her as a level 2 boss, and with a d6 ofr damage and only 4 HP that is mostly true. If not dealt with swiflty though, her and her legion of angels would quickly outpower a group of level 2 adventurers. This inspires some interesting potential. Do the PCs stick it out and try to overcome her at this point, or do they run away and regroup, and try to catch her unaware when she has cooled off?

Instants and Sorceries

GMs should use these similar to how they are used in MtG, as effects that can be activated, in the rooms. Instants are considered single time effects a character controlled by the GM can use, but sorceries can be recharged.

To recharge a Sorcery, roll a d10 at the beginning of the turn. If you roll over the casting cost of the spell, it has been recharged.

If the effect of the Instant or Sorcery is something the PCs are able to resist (Intimidate, for example), the DC of the save is equal to 10 + the total casting cost of the card.

Narratively, more often than not, the Instants and Sorceries will help to make creative creatures, and should be considered actions they are taking (usually on their turn). In a case where there are no creatures in a room but the GM still has cards to play (as it were), think about making these actions qualities of the space instead.

Artifacts and Enchantments

There are multiple types of artifacts and enchantments, so they can be interpreted a few different ways, but are the main card types that can be associated with gear or treasure in most rpg systems. Artifacts are also the most varied in terms of how they might translate, and may require the most creativity in adaptation, but also have the most potential for fun shenanigans! Some ideas for using artifacts and enchantments below:

Equipments and Auras can attach to creatures to change their stats and abilities. Artifacts that are attached to a creature could be also be dropped as loot.

If the artifact is a tool that has an activation, make it a feature of the room that the GM and the players can activate. Or a trap.

When all else fails, take the card art and flavour text and use it to add detail and narrative to your dungeon.

Appendix A: Keywords + Abilities

Add mana - Mana can be exchanged for health at a 1 for 1 rate.

Enter the Battlefield - treat these effects as option first turn actions for the monsters, or have these creatures enter the room later in the battle and trigger these effects.

Draw cards - If your deck still has cards available in it, draw the appropriate amount and increase this rooms resources.

Counter - Impose disadvantage

Exile - Phase to another plane/character unable to act for 1 round

Mill - Exchange cards in hand for cards in deck

Sacrifice - kill it

Tap target creature - entangle PC on failed save

Scry - creatures who scry cannot be surprised and should have an advantage on the PCs.

Destroy -

Attach - upgrade a creature in some way

Deathtouch - poison residual damage each turn unless healed

Defender - do not attack, do dmg when attacked

Double Strike - 2 attacks

First Strike + Haste - always goes first in initiative

Flash - hidden until relevant moment

Flying - creature can fly and assumed basic attack is ranged.

Hexproof - spell resistance - disadvantage on attacks with spells

Indestructible - damage resistance - disadvantage on attacks with weapons

Intimidate - Save vs Fear

Lifelink - heals on attack

Menace - can attack 2 different targets per turn

Protection - resistance of a type - half damage or system appropriate rule White - lightning + air Black - poison + necrotic Red - fire + heat Blue - cold + water Green - acid + stone

Prowess - empowered by spellcasters, gains +1

Reach - extended reach - default to 10 ft

Trample - cleave damage - will hit next character with overflow if present

Vigilance - double toughness