Island Discovery / Campaign Diary: Archipelago Adventures - Pt. 11

We have finally done it, we are about to discover an island. Are your hands shaky? Cause mine are… but that’s only cause we get to roll more dice!

Thanks to Caleb… we have a name for our island, Munta. This fantastic island could be anything for our players. Or it could just be a large rock sitting in the middle of the ocean. I’m open to any possibility for them. But let’s go back to our beautiful map.

Day 10

On our 10th day, we sail from Hex 8 (where the ship is on) to Hex 10 (the dark green hex) and we discover our island. Because we have made our previous Navigation rolls to find this island, I’m not going to worry about a Navigators check to make sure we land on the island. I may change my opinion on that, but for now, let’s go with no check for the final hex.

So our ship gets to the final hex and we have a few questions going for us; like… When do we find it? How big is this island? Will we die if we go onto this island? If an island exists, but nobody ever visits it… does it really exist?

Let’s start with the first question, when do we find it?

I think for that question, we can go back to the article on Encounters and use the time of day system and treat this island as an Encounter. This means, we roll a d6 to determine what time of day it is.

Roll / Time Result / Abstract Result
1 / 1am - 4am / Night, Moon is out, Darkness
2 / 5am - 8am / Early Morning, sun begins to rise, Dim Light
3 / 9am - 12pm / Late Morning, sun is fully up, Bright Light
4 / 1pm - 4pm / Afternoon, sun is fully up, Bright Light
5 / 5pm - 8pm / Early Evening, sun begins to set, Dim Light
6 / 9pm - 12am / Late Evening, Moon is out, Darkness 

This means on a d6, we determine how long we had to travel before we find our island. This can be pretty important for our impatient explorers. If we arrive at night, this can help us keep out of sight in case of hostiles, on the other hand… it means we pry aren’t going to explore the island at midnight… I can’t think of anything creepier than exploring an unknown island under a full moon. Luckily for my nerves, I rolled a 3 which means we find this island in the Late Morning, with the sun fully up and bright light to guide us!

Which brings us to the next dilemma, how big is this island?

Ginormously Small

The question …in a randomly generated island adventure, how do we create an island out of nothing? The answer… I get to create a lot of islands… hopefully with your help. See, my vision for this is that I will have a hundred islands to work with (and stat up) for this purpose. There will be a d100 chart (each island gets a single digit assigned to it) and our GM gets to roll on it. Now… that’s a lot of islands to have prepared, but I’ve thought of that too, and will be something we talk about next week.

Today, lets go over the basics, we need:

Size of the Island
Population of the Island
Tier Level
Resources

Let’s begin with the Size of the Island… Islands have no set size to them. Some are tiny islands with only a few acres on it, others are massive and some people even call them a continent. I think we can safely take out any massive continent size islands and focus on something a bit smaller for our party to explore. 5e assumes an average travel speed of 3 mph when walking about (this is 30’ per round), this means that in 8 hours a party can travel 24 miles in one go. A 24 mile long island is pretty big, especially if it is also 24 miles wide, this gives them 576 square miles of area… that’s a lot. That would take our party 24 days to walk through every mile of the island. I think we can safely make 24 miles our largest size for our islands, now on the opposite side I think our smallest islands should come in at 2 miles. This gives them about 40 minutes of walking to get from one side to the other, and feels like an appropriate amount of reason to get off a boat and explore a land mass…. its more than a sandbar at least.

Now… I also have one more reason why it should be a minimum of 2 miles… there are no 24 sided dice, but there are two dice that make up 24… well, more than two dice really. This can be achieved with:

d20 + d4  /  2d12  /  2d10 + d4  /  3d8  /  6d4  /  4d6

This isn’t something that the GM running the adventure would ever have to figure out (unless they want to make their own island) but it helps us when it comes to figuring out the sizes of our islands. I want to figure out what the average size of an island should be, and then figure out the size for the rest of the islands. Each combination of dice is going to get us a similar result for the average, so we are pretty good to use any combo:

d20 + d4 (avg 13)  /  2d12 (avg 13)  /  2d10 + d4 (avg 13.5)  /  3d8 (avg 13.5)  /  6d4 (avg 15)  /  4d6 (avg 14)

This tells us that islands should be at least 13 x 13 miles, a suitably sized island with about 169 miles to explore… Half a day to travel from one side to other, which, at least to me, feels like an island. Something large enough to get lost on, but not so large you’ll never be too far from shore.

But what is the frequency for the different sizes of islands? If we go over to anydice and have it calculate 2d12 as a bar chart, we can see that 13 will be the result 8% of the time with the other numbers quickly falling in likelihood the further they get from 13, and our extremes 2 & 24 only appearing .69% of the time.

So Much Math

Now, this is a lot of math, and I don’t blame you for giving up on me right now. I’m just blathering on about dice and miles and percentages without answering the question of how big is this fucking island? We don’t need to be going this deep into it, and frankly… even I’m getting confused about all this. I just wanted to know what the average for finding a certain size of an island, and I have my answer, the average island (10-16 miles on one side) has a 50% chance of showing up. After that, it gets smaller very quickly, so let’s go ahead and create 3 categories for island size and we will deal with specifics later:

Small -> 9 miles or smaller (on one side)  /  25%
Medium -> 10 - 16 miles (on one side)  / 50%
Large -> 17 miles or larger (on one side)  /  25%

Now, from here on out, I am going to simplify the rest of the numbers. I dont know why, but I feel that it is more important to have an understanding of what size the island might be than to number the exact population of an island. If you have any questions, please ask away!

Population

This can go all over the place in terms of population density, but the larger the population, the island should be larger too. I think we can base the population on each island based on the size of the island, we will break this out into three categories and have there be a chance that an island may have more or less population than the average island of its size.

Sparsely Populated -> Small (75%) or Medium (25%)
Moderately Populated -> Small (25%) or Medium (50%) or Large (25%)
Plentifully Populated -> Medium (25%) or Large (75%)

Tier

Because we are planning on having a level 1 to 12 sea adventure, we only have three main tiers to work with. Tier 1 (level 1 to 4) will be mostly in Colial and the surrounding islands, Tier 3 (level 11 to 16) will be focused on finding the BBEG and stopping them, which leaves Tier 2 (5 to 10) as the main bread and butter of our sea adventure. Let’s go ahead and assign those tiers percentage of the islands that belong to them:

Tier 1 -> 20% of Islands  /  2 levels (3 & 4)
Tier 2 -> 60% of Islands  /  6 levels (5 - 10)
Tier 3 -> 20% of Islands  /  2 levels (11 & 12)

Resources

Now, the last thing we need a quick reference for is… what are the resources of these islands? I assume some may have no resources, others have a huge amount and other islands are similar to others. Let’s go ahead and assign them quick numbers:

Barren -> 25%
Fertile -> 50%
Lush -> 25%

Adding It All Together

Now, all of these separated doesn’t make a lot of sense, and quite frankly a lot of these numbers are just what feels right for the situation, and highly simplified. But I went ahead and threw them all into a spreadsheet to get an idea as to what everything will look like. This is not set in stone as to what our islands will look like, but its nice to have a visual representation. Plus, if we ever get stuck, we can always make a random island based off of that.

And I think… this is where we are going to leave for today. Next week, we will skip all this math nonsense and get into designing and create Munta, the next island! I'm pry going to make another chart too... oh oh and maybe discuss island design, and maybe we can talk about inhabitants, and... well... I think we are going to be on islands for a while.

Goblin/Hobgoblin Warship

Tier 1 - Keelboat, 2d6 goblins will attack by boarding the ship led by a Hobgoblin Captain. They will attempt to flee if half their number is reduced and they can access their ship, and the Hobgoblin Captain is killed.
Tier 2 - 1d4 Keelboats, each Keelboat has 2d6 hobgoblins who will attack by boarding the ship, each is led by a Hobgoblin Captain. They will attempt to flee if half their number is reduced and they can access their ship, and most of the Hobgoblin Captains are killed.
Tier 3 - Sailing Ship, 2d12 hobgoblins will attack by using their mangonels to knock out any weapons and then the sails before boarding the ship, they are led by a 1d4 Hobgoblin Captains with a Hobgoblin Warlord in charge of everyone. They will attempt to flee if they lose their weapons, their ship is reduced to half health or they lose half their men if they are able to access their ship.
Tier 4 - Warship, 5d20 hobgoblins will attack by using their mangonels and ballistas to knock any weapons and then the sails before boarding the ship, they are led by 2d6 hobgoblin captains and a Hobgoblin Warlord. They will attempt to flee if they lose their weapons, their ship is reduced to half health or they lose half their men if they are able to access their ship.

Treasure: While the most treasure each ship has is based off of food rations (enough to feed their crew for 1 month), they also carry an assortment of trading goods and valuable prizes. See the chart below.

Tier 1 - Treasure Hoard 0-4 (pg 137, DMG) / Ignore any magical items rolled
Tier 2 - Treasure Hoard 5-10 (pg 137, DMG) / Ignore any magical items rolled
Tier 3 - Treasure Hoard 11-16 (pg 138, DMG) / Ignore any magical items rolled
Tier 4 - Treasure Hoard 17+ (pg 139, DMG) / Ignore any magical items rolled