Tag Archives: Ryuutama

Ryuutama miscellany

Following are a few miscellaneous mechanical ideas gleaned from Ryuutama which may be worth adapting or hacking into your D&D-alike edition of choice.

Initiative is AC

At the start of combat in Ryuutama, each player character rolls initiative, which is DEX + INT. Recall that abilities are dice, with d6 representing average, so this roll is something like 2d6 or d6+d8. The value obtained both determines order of action and defense value (basically, AC). An equipped shield provides a minimum defense value (7 for small shields and 9 for large shields). This makes both initiative and shields more influential without contributing to numerical inflation (as happens with the arms race between AC bonus and attack bonus for many versions of D&D).

In addition to equipping a shield, player characters can use an action to re-roll initiative, taking the new result if it is better. So, a bad initiative roll does not spell doom, though it can slow a player character down (which seems appropriate for initiative).

Initiative also controls retreat

Even among those woke to the virtues of morale checks, in my experience it is easy to slip into fighting to the last combatant. This may play into the reasons for retreat rules either being somewhat complex or perhaps just untested. In any case, the Ryuutama approach here is both simple and surprisingly harsh when followed to the letter, given the suggested heartwarming tone. The rule is that travelers can retreat if the sum of their initiative values is equal to or higher than the sum of enemy initiative values. This means that once enemies gain an advantage, it may become very difficult, or even mathematically impossible, to run away.

That math may be less than ideal, depending on your intention for combat dynamics, but I like the idea of using initiative to manage retreats. Another, slightly more flexible approach for Ryuutama along similar lines—that I may use the next time I run Ryuutama—would be to have the entire party make a new group initiative check to determine whether running away is possible. This would hold out a sliver of hope, even if several travelers were down and the sum of enemy initiative values was high.

This is even easier to hack into another game if using side-based d6 initiative, though it is a bit more random. When the player characters win initiative they can simply declare retreat and it happens, as long as there are no obvious fictional constraints such as a bridge being out. Similarly for monsters. Then, if one side or the other wishes to pursue, chase rules would come into play.

Battlefield abstraction

Ryuutama battlefield (PDF here)

As in many classic JRPG video games, combatants are either in the front or rear rank. Combatants in the front rank may be targeted with either melee or ranged attacks while combatants in the rear rank may only be targeted with ranged attacks. Any area effects attack all combatants in the front ranks, either allied or opponent. If all the combatants in the front rank are defeated, the remaining combatants in the rear move into the front, meaning that it makes sense to maintain several frontline defenders if possible, though one will hold the line.

This is elegant (and plays nicely based on my limited experience so far). The structure maintains enough tactical complexity to model offensive and defensive fighting without resorting to bonus math; further, it requires minimal bookkeeping. I was originally somewhat wary of the structure feeling artificial and constraining tactical infinity, but in practice our fictional battlefield and the tactical schematic coexisted without conflict. This approach could be lifted verbatim, I think, into a B/X game.

Ability checks draw on two abilities

In Ryuutama, any ability check uses two abilities. In all versions of D&D that I am familiar with, ability checks use only one stat, such as strength. Using two abilities leads to a surprising degree of mechanical richness, however, and would be particularly easy using the ability bonus scale of B/X, which is 13-15 = +1, 16-17 = +2, and 18 = +3. This, two relevant 18 stats yields only a +6 bonus, well within the scope of modern bounded accuracy approaches. This would be most straightforward when using roll high versus DC style ability checks but easy with roll-under checks too (just allow the bonus of one ability to increase the value of the other ability, for purposes of the immediate check).

Condition modulates poison etc

Traditional D&D often uses save or die for poison. This works well enough, but requires some care on the referee side. It is, however, abrupt. Many alternative approaches soften the blow by providing various additional buffers, such as having poison do damage or applying other effects. Generally, this makes poison either a mere distraction or an additional thing to track.

The approach in Ryuutama is to make poison, and other similar conditions, only affect travelers with condition less than or equal to some set value. (Condition in Ryuutama is sort of like mood and travelers re-roll it each day.) The effect of poison in Ryuutama is to decrease strength by one die type. A D&D analogue might be disadvantage to attack rolls and physical ability checks, with the modulating factor probably being HP; for the threshold, something like 25% or 50% max HP might work. Though this certainly makes poison less immediately terrifying than save or die, I kind of like it.

The Ryuutama engine

A while back, I posted about the OD&D game engine. I think that post was helpful to me at the time for understanding how OD&D the game worked at a mechanical level. As I have been reading and enjoying Ryuutama recently, a similar exercise may be informative. This exercise may also provide a good intro to Ryuutama for players familiar with traditional D&D.

There are several broad, generally applicable rules systems: travelers, incentives, journeys, setting, combat, and the ryuujin. I will only focus on the first four of those systems here because they seem most integral to the core engine.


These are the rules for player characters, which Ryuutama calls travelers.

Travelers have three major mechanical underpinnings: classes, type, and ability scores. Class in Ryuutama is more like background in many other games, and provides a set bundle of skills. Example classes are merchant, hunter, and farmer. Travelers get one class at first level and another at fifth level (max level is 10). Type, however, is more like what class means for other games, and can be one of attack, technical, or magic, which map, respectively, to the traditional classes of fighter, thief, and magic-user. There are four ability scores: strength, dexterity, intelligence, and spirit. Ability scores are measured in dice, with d6 seeming to be about average, d8 being one step higher, and so forth. Travelers also have three state variables: hit points, mental points, and condition (a value that fluctuates daily and is sort of like mood).

The major resolution system is the check, which involves rolling two ability dice (sometimes both are the same ability), adding the results, and comparing the sum to a target number (like a difficulty class in D&D terms). For example, accuracy with a blade (basically, rolling to hit, which is based on weapon type) is DEX + STR. Trapping, a hunter skill, uses DEX + INT. Target numbers range from 4 up. The text labels 7 as a little difficult and 12 as very difficult, to provide some orientation.

  • Class: artisan, farmer, healer, hunter, merchant, minstrel, noble
  • Type: attack, technical, magic
  • Ability scores: strength [STR], dexterity [DEX], intelligence [INT], spirit [SPI]

There are a few other details such as favored weapon, carrying capacity, and so forth, but the rules mentioned above are the foundational components. You can check out the full character sheet as well.


Similar to most traditional fantasy games, characters increase in power through gaining levels, and gaining levels requires XP. Concretely, increasing level improves an ability, provides some extra HP or MP, and provides a few other perks depending on which level.

Ryuutama awards an amount of XP each session based on the highest topography target number (more on this in a moment) encountered, the single most powerful monster defeated, and for each benediction (GM-PC power) the referee used.

I like this approach overall because it rewards seeking out challenges and requires minimal bookkeeping. It is generally relatively easy to recall the single most powerful monster and there is no need to track the exact number of orcs or whatever. Further, though the marginal benefit may be small, the game will always reward tackling a more powerful monster or more dangerous environment within a given session.


The journey procedure is a loop that the party engages to move from one fictional place to another. In sequence: condition checks, travel checks, direction check, and finally camping check. The final three checks all use terrain + weather as the target number. Each traveler makes a separate condition and travel check, but the mapper (one traveler designated by the party beforehand) makes a single direction check for the entire party. A single camping check applies to the entire party as well. The travel check is kind of a big deal, because failing it halves the traveler’s HP (which is about as important in Ryuutama combat as it is in traditional D&D combat, though the halving procedure suggests quite a bit more abstraction in Ryuutama compared to what many players assume about HP in D&D).

For each of these journey checks you end up rolling a pair of ability dice (added) versus an objectively determined target number; for example, grasslands = 6, deep forest = 10, strong wind = +1, and hard rain = +3. So, travelers journeying through deep forest in the hard rain will be rolling against a target number of 13.


Travelers journey between places and encounter things. What determines the details of towns, what lies between them, and what challenges relevant to the travelers exist?

Within the setting rules are guidelines for creating the world at a high level, towns, scenarios, and events. These rules are more elastic than other systems and read more like a set of suggestions than a tight set of procedures, though there are worksheets for each (town, world, scenario, event) with prompts, along with the invitation to maybe work through the process collaboratively with players. For example, the town worksheet has spaces for representative building and specialty goods.

Though not explicitly stated procedurally, several aspects of the rules gesture toward the idea of building up the world organically as journeys unfold, while leaving space for some more traditional lonely-fun referee world-building. There is a grid map sheet that players could fill in as travelers journey. The rules suggest an option where all the players design the town for the next session at the end of the current session and place it on the map, indicating what interstitial areas the referee should focus on in preparation.


The ryuujin (GM-PC guardian angel) rules also seem important for running a game of Ryuutama in the expected mode, due to how they support the referee intervening in a limited way to shape the story. However, the ryuujin rules are tied less tightly to the core engine, as far as I can tell, apart from the XP reward for using benedictions as noted above, and so I will end here. See this post for a bit more on the ryuujin rules, if you are curious, and also the ryuujin character sheet.

Eidolon mode

Ryuutama mechanizes a limited degree of referee fudging through a conceit where the referee plays a character called the ryuujin. In translation, this means dragon person, and represents an entity somewhere between minor deity and guardian angel. The ryuujin exists within the fictional world, but in practice stays mostly offscreen. It is actually a character though, with a record sheet, life points, powers, level, and so forth, though the applicable rules for a ryuujin are different than those for player characters.

Mist dragon summon from Final Fantasy 4 (SNES)

In Final Fantasy 4, the character Rydia is a caller, a kind of magician that can summon Eidolons, or Call Beasts, to fight for the party. In Final Fantasy 6, espers are powerful magical entities that once defeated can be summoned. Systems exist for summoning in many Final Fantasy games.

Can you see where I am going with this?

A similar structure could be used for a powerful supernatural ally such as a bound demon, sandestin, or summoned creature. For players used to a more limited scope of narrative influence and narrower tactical challenge, the ryuujin rules can seem to be something between easy mode and cheating. However, that interpretation may be more driven by tone rather than mechanics. With slightly different flavoring, and possibly exposing more aspects of the ryuujin record sheet to the party as a whole, similar rules could support access to something like summoning an esper. Consider also the possibility for something like a mech or titan form (Attack on Titan, Voltron, etc).

Mechanically, Ryuutama gives the ryuujin several capabilities, including benedictions and reveils. Benedictions are powers that a ryuujin can use by spending life points and have effects such as rewinding a small amount of fictional time or declaring a particular check to be a critical success. Some benedictions create obstacles for players, such as increasing monster power or allowing an enemy to run away without needing to satisfy any conditions, presumably in support of guaranteeing certain story elements. In a reveil, the ryuujin appears in dragon form and saves the players in some specific way, such as manifesting to take the damage intended for a player character. Even when representing something like a summoned ally more under the control of players than is the ryuujin, the entity could maintain a degree of autonomy, also causing complications for players occasionally.

Evangelion / Voltron / Attack on Titan

Some of the ryuujin rules are attempts to mechanize a limited degree of referee discretion while maintaining some impartiality. Others are explicitly for rescuing and assisting the travelers, essentially decreasing the stakes in pursuit of the intended tone, which is low-arousal, calming, and heartwarming (honobono, in Japanese). However, with a slightly different set of priorities, similar rules could mechanize access to limited supernatural heavy artillery that players could deploy a few times per session.