Fabula Ultima - Matty's Immram Mini-Game

29 Sep, 2025

I introduced a mini-game to my tabletop group in our last session of Fabula Ultima. Each session an NPC friend of the party gets swept away to a fairy see, visits a handful of strange islands, and returns with a haul of treasures she can trade to the party. The game shines a spotlight on a character the party effectively invented and allows me to play with the Immram framework of stories, which is fitting for our game's JRPG Arthuriana theme. If you are familiar with the middle-parts of The Odyssey or with C.S. Lewis' Voyage of the Dawn Treader then you have a good picture of what this looks like.

With the understanding that these rules are subject to change as we play and find their deficiencies, here's how Matty's Immram currently works!

Steps

Step 1 - Generate Matty's Stats. The party collectively generates Matty's statistics, specifically focusing on Ability Scores and broad roles instead of specific Fabula Ultima classes. Matty starts at level 1 and her Hit Points, Mind Points, and Item Points are generated from her Ability Scores in the same way any character's are in Fabula Ultima.

Step 2 - Invest in the Trip. At the start of each session Matty is magically swept away to The Mirrorlight Sea, a fantastical fairy sea. When she is, the players can choose to invest zenit into the voyage to either extend the maximum possible length of her trip by one site and/or guarantee they receive one treasure at random from the treasures Matty finds while traveling.

Zenit values are based off of party size and level. My campaign features five player characters, so for levels 5-9 they are expected to receive 1,000 zenit each session. I went with my gut and decided that spending one-fifth of that to extend the trip is reasonable. I initially went with that for investing to receive a treasure as well, but upped that to two-fifths because it gives me more leeway for designing treasures for Matty to find. More on designing treasure below.

Step 3 - Resolve The Existing Conundrum. At the end of each trip Matty is confronted with a Conundrum, which she in-turn presents to the party, asking for advice on how to resolve it. If the party provides advice that seems good or reasonable, Matty resolves the Conundrum in this step and adds a treasure to her haul for this trip. If the advice is poor, then Matty circumnavigates the Conundrum safely but does not add a treasure to her haul.

Step 4 - Determine How Many Sites Matty Can Visit. The players roll 1d4+1 to determine the maximum length of Matty's trip. If they invested zenit back in Step 2 to extend it, they extend that length by one. I went with 1d4+1 or +2 because it feels like a reasonable length for a mini-game meant to be resolved quickly in a session. Any less than two sites and folks feel bad if the first site fails and Matty returns home. Any more than six and it starts to take too long or require me to generate more sites to visit and treasures to find than I want to.

Step 5 - Generate a Site. Matty sets sail. The Mirrorlight Sea is broken into regions, and each region roughly corresponds to a level range. Matty always starts in the region she ended the last session in unless she found a site that unlocked a new region, in which case she starts in that new region. Each region is has a theme that informs the kind of sites found in it.

For each site Matty visits I roll 1d4 + Matty's level two times and consult a weighted d44 table to determine what she finds in the region she is in. Each region's d44 table uses different values, with new regions generally being five levels higher than the last. Each site table is weighted so that by the time Matty reaches the level cap of the region she will have found a path into the next region.

Here is an excerpt of the d44 table for the first region of The Mirrorlight Sea, the Silver Lens Shoals region. Note that a 2- denotes I rolled a two-or-less and a 6+ denotes I rolled equal to or above 6. Matty can find a route to a new region on a roll of 6+6+ (the level of the region plus five). That creates a chance of entering a new region below its recommended level. While not possible in this first region, I still annotated the lowest value as 2- to represent rolling too low for a given region.

As an example, we start a new trip. Matty is level 1, so I roll 1d4+1 two times and get a 2 and a 3. Her first stop is the Cloudwalking Giant!

To design the sites I made an oracle table to generate prompts to build off of. The first column are themes for the region and the second are broad categories of people or places encountered in Immram or questing knight stories.

To use the Backwards Giant as an example, I rolled a 3 for Theme and 3 for category - a backwards giant. I then interpreted it this way:

Cloudwalking Giant. Grows upside down. Takes offense to Matty stomping on or sailing across his "ceiling."

Step 6 - Visit the Site. When Matty visits a site she adds a treasure to her haul and then faces a skill challenge. Each challenge is a flat check against a difficulty level 10. On a success nothing bad happens; On a failure Matty loses some amount of either Hit Points, Mind Points, or Item Points. I am using the Heavy Damage value for Hit Point and Mind Point damage and arbitrarily picked three for the Item Point damage value. Using Cloudwalking Giant as our example again, the rest of the site entry looks like this:

Cloudwalking Giant. Grows upside down. Takes offense to Matty stomping on or sailing across his "ceiling." Roll [INS + WLP] DL 10 to convince him you are just dusting the ceiling. On failure, lose 30 HP.

Step 7 - The Next Site. After a site is resolved decrement the number of sites Matty can visit by one and check her resources. If her site counter, Hit Points, Mind Points, or Item Points are zero she ends her trip and we move onto step 8. If she still has sites left to visit and none of her resources are tapped out, repeat steps 5 through 7.

Step 8 - The Conundrum. The last thing that happens to Matty on a trip is the Conundrum. This is an open-ended puzzle she asks the party for help with. Note the party's answer down for the next trip, where the Conundrum will be resolved. See step 3 for more details.

I ran out of time so have not generated a list of Conundrums yet. The bespoke one for the first session was:

The ship is forced aground by the splash of a giant, rainbow-scaled tuna that became fascinated by the ship and refuses to stop playing with it. How can Matty bypass the playful, prismatic tuna titan?

The party suggested she distract it with something shiny or reflective, like a mirror. This seems reasonable to me, so next session Matty will find an additional treasure during step 3.

Step 9 - Treasure. After determining the conundrum, Matty is magically whisked home with her treasure haul. The haul contains one treasure for each site visited and an additional one if the conundrum was satisfactorily resolved. Matty then can sell the treasures to the party. If the party invested to receive a treasure, they receive a randomly picked treasure from the haul.

Treasures are weapons, armor, accessories, or similarly useful items. I currently design or pick the items with values ranging from half-of-the-investment-cost to twice-the-investment-cost. For example, the party invested 400 zenit to find a treasure and my pool of items were valued at approximately 250 zenit to 600 zenit. This makes investment a bit of a gamble - maybe you get something worth more, maybe you get something worth less.

I didn't have time to build a full table for this last session, so instead I created a few and randomly determined the order Matty found them in. Going forward I hope to create a table to roll on. As items are bought I will remove them from the table and replace them with something new.

Any treasures left over after are sold or given away so that there is clean haul next session. I don't particularly want to track what the party didn't buy on the off-chance they decide to buy it later.

Step 10 - Gain XP. Matty gains 5 experience points for the trip. Every 10 xp her level increases by one, same as with player characters. This improves her Hit Points and Mind Points and likely will improve her ability scores down the road as well.

And that's it for now. One session into the Immram it is going well. The three things I'm keeping an eye on for now are how the players react to not having enough zenit to buy every treasure they want; whether I should increase Matty's level, and therefore her HP and MP, so she doesn't get sent home too quickly; and whether conundrums actually add anything to the mini-game. My players also hinted at giving Matty character levels, so she could end-up with specific classes in the future. Keep an eye on my play reports to see how things go!

#fabula ultima #mini-game #minigame #rpg #the romance of ys #ttrpg