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Coronoides

Navigation and ocean crossings

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Crossing an open ocean like the Pacific or Atlantic is tricky buisiness without a way to measure longitude and with the western Iron Age/medieval  ships provided in Magic World. The rules as printed are fine for island hopping and coast hugging but if you want to emulate Columbus or Leif Erikson then some house rules are needed. Here is my first pass anyone have any suggestion or spot any mistakes?

Firstly, based on historical examples a seaworthiness of at least 22 is recommended and even then if the weather turns bad there is a good chance you will sink. Really big warships are not recommended because they lose seaworthiness to fast and  can't carry enough supplies to feed and water their large crews for the duration of the crossing.

Houserule: Here we assume navigation rolls at sea (MW135) are made weekly rather than ‘per trip’. Out of sight of land longitude can only be figured by error-prone dead-reckoning so halve navigation skill. If out of sight of land and 3 or more days in the week have complete cloud cover then halve navigation skill again. Remember at sea effective navigation skill is never higher than the navigator’s sailing skill (MW42).

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It depends really.

Are you trying to navigate to get somewhere particular? If so, you would probably have some way of tracking the route, maybe by stars, islands, ocean currents or whatever, so you would use those as navigation guides. So, I wouldn't halve navigation, unless you have nothing to use as a guide.

If you are exploring open water for the first time, them you only need Navigation to work out roughly where you are. Many explorers in the real world had really no idea of where the places were that they went to. Several places were rediscovered by later sailors.

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On 12/19/2018 at 5:47 AM, Coronoides said:

Crossing an open ocean like the Pacific or Atlantic is tricky buisiness without a way to measure longitude and with the western Iron Age/medieval  ships provided in Magic World. The rules as printed are fine for island hopping and coast hugging but if you want to emulate Columbus or Leif Erikson then some house rules are needed. Here is my first pass anyone have any suggestion or spot any mistakes?

 

Firstly, based on historical examples a seaworthiness of at least 22 is recommended and even then if the weather turns bad there is a good chance you will sink. Really big warships are not recommended because they lose seaworthiness to fast and  can't carry enough supplies to feed and water their large crews for the duration of the crossing.

The problem with that, is that you don't get ships with 22 seaworthiness until later. Columbus' Nao's didn't have it, and Erickson's Longships certainly didn't. 

On 12/19/2018 at 5:47 AM, Coronoides said:

Houserule: Here we assume navigation rolls at sea (MW135) are made weekly rather than ‘per trip’. Out of sight of land longitude can only be figured by error-prone dead-reckoning so halve navigation skill. If out of sight of land and 3 or more days in the week have complete cloud cover then halve navigation skill again. Remember at sea effective navigation skill is never higher than the navigator’s sailing skill (MW42).

What are you trying to accomplish here? 

Let's go over what you are accomplishing in terms of game mechanics and tell me if it's what you are trying to do:

Assume you have a navigator at 100% skill. He's out of sight of land so his navigation skill get's halved, twice. So now he's down to 25%. If it takes him at least two weeks to get to where he's going he would need to make two rolls, so he'd have a 6.25% chance of success. This is probably your best case scenario. Most people will be much lower, and or the trips will be longer.

It would be much simpler, and nicer just to make one roll per trip at 5%.  

Is that what you wanted?

 

 

 

 

 

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5 hours ago, soltakss said:

It depends really.

Are you trying to navigate to get somewhere particular? If so, you would probably have some way of tracking the route, maybe by stars, islands, ocean currents or whatever, so you would use those as navigation guides. So, I wouldn't halve navigation, unless you have nothing to use as a guide.

If you are exploring open water for the first time, them you only need Navigation to work out roughly where you are. Many explorers in the real world had really no idea of where the places were that they went to. Several places were rediscovered by later sailors.

Good points. Thing is during ocean crossings even if you have a destination in mind, say Vinland, you don’t have much to go on. The stars are a help but even then longitude was a notorious issue. the West Coast of Australia was struck by several Dutch navigators trying to get to India. Looking at a map of the globe that’s a big north/south mistake. Open ocean crossings you have the stars if the weather is good.  The rediscoveries by later sailors you mentioned show just how hard ocean navigation is. However, as an explorer if you find something good you want to try to get back there so navigation is important. 

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4 minutes ago, Coronoides said:

Good points. Thing is during ocean crossings even if you have a destination in mind, say Vinland, you don’t have much to go on. The stars are a help but even then longitude was a notorious issue. the West Coast of Australia was struck by several Dutch navigators trying to get to India. Looking at a map of the globe that’s a big north/south mistake. Open ocean crossings you have the stars if the weather is good.  The rediscoveries by later sailors you mentioned show just how hard ocean navigation is. However, as an explorer if you find something good you want to try to get back there so navigation is important. 

Sure, but with the quartering of skill and multiple rolls you end up making the skill worthless. 

 

I'd suggest, halving skill when out of site of land. Just once. Then add in a luck roll and the results of both rolls determine how far off course they are. If the player critical both then, surprise they are pretty close to where they wanted to be (say within 1% of the distance) go from there. Say within 5% for success, 25% for a failure and 50% for a fumble. SO double fumble means anywhere with 100% of the travel distance!

 

 

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3 hours ago, Atgxtg said:

The problem with that, is that you don't get ships with 22 seaworthiness until later. Columbus' Nao's didn't have it, and Erickson's Longships certainly didn't. 

What are you trying to accomplish here? 

Let's go over what you are accomplishing in terms of game mechanics and tell me if it's what you are trying to do:

Assume you have a navigator at 100% skill. He's out of sight of land so his navigation skill get's halved, twice. So now he's down to 25%. If it takes him at least two weeks to get to where he's going he would need to make two rolls, so he'd have a 6.25% chance of success. This is probably your best case scenario. Most people will be much lower, and or the trips will be longer.

It would be much simpler, and nicer just to make one roll per trip at 5%.  

Is that what you wanted?

 

 

 

 

 

I’m a bit rough on the history of the American colonies but I thought that Erikson would have had a Knorr (Seaworthiness 22) and Columbus something at least as good as a Small Cog (Seaworthiness 22). A knorr being a merchant ship with good cargo space seems like a more likely exploration and colony ship than a longship built for war.

I am trying to model the fact that open ocean crossing, especially before good clockwork enabled the determination of longitude was difficult.  Furthermore ocean voyages took a long time, plenty of time to get lost. The Europeans travelled to India in the Middle Ages because that was a coastal route. The Americas across the open ocean even after discovery by Erikson were not frequently travelled to, so much so that Columbus got to discover them again. 

As written above Navigation skill is halved once for being out of sight of land. It is halved again only if there is complete cloud cover for several days in the week. 

The per week was to make longer journeys harder than shorter trips. Now as Soltakss pointed out if you sail west and you are just trying to hit the continents of the America’s that’s easy. However, if you are trying to resupply your colony in Vinland or Van Diemen’s Land then ideally you’d sail into the right bay. Magic World provides no standard method of making unopposed rolls more or less difficult, hence my halving but I accept that may be too harsh. Still the idea is it takes a extremely skilled navigator to do it. Similarly, weekly may be too frequent. Perhaps monthly? Remember that all this is only while out of sight of land.

I envisage an ocean crossing is an adventure in it’s own right. A single navigation roll, like a single random encounter roll is unsatisfying. 

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18 minutes ago, Atgxtg said:

Sure, but with the quartering of skill and multiple rolls you end up making the skill worthless. 

 

I'd suggest, halving skill when out of site of land. Just once. Then add in a luck roll and the results of both rolls determine how far off course they are. If the player critical both then, surprise they are pretty close to where they wanted to be (say within 1% of the distance) go from there. Say within 5% for success, 25% for a failure and 50% for a fumble. SO double fumble means anywhere with 100% of the travel distance!

 

 

I was writing the above as you were writing your reply. So yes as per the way my original proposal was written most of the time you halve navigation once. I really like the luck roll idea and your idea to provide for differing levels of success. Note being 100% out by double fumble would explain all those early Dutch merchants trying to get to India and crashing into the West Coast of Australia!

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So with all your help a revised version looks like this...

House rule: Here we assume navigation rolls at sea (MW135) are made once per month (or part thereof) rather than ‘per trip’. Out of sight of land longitude can only be figured by error-prone dead-reckoning so halve navigation skill. If out of sight of land and 14 or more days in the month have complete cloud cover then halve navigation skill again. Remember at sea effective navigation skill is never higher than the navigator’s sailing skill (MW42). If out of sight of land also roll Luck. For navigation out of sight of land compare the results of the Luck and navigation rolls to below:
•    For each Fumble your location at is 50% of the travelled distance away from the intended end point for the month (or part thereof).
•    One success negates a fumble and your location at is 25% of the travelled distance away from the intended end point for the month (or part thereof).
•    Two successes places your location at 25% of the travelled distance away from the intended end point for the month (or part thereof).
•    A special success reduces the % distance of your error by 10%.
•    Two specials places your location at 5% of the travelled distance away from the intended end point for the month (or part thereof).
•    A critical reduces reduces the % distance of your error by 20%.
•    Two criticals places you exactly where you expected to be at the end of the month (or part thereof). 
When navigating out of sight of land most errors are in the north-south axis.

I’m still happy to hear further suggestions.

 

 

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4 hours ago, Coronoides said:

I’m still happy to hear further suggestions.

1) Put into a table so you can give the player/GM one final % number

2) Skill should probably be worth more than luck. So a successful Navigate should probably be worth more than a successful Luck roll.

3) Factor in something for prevailing winds and currents. From what I recall the easy way to cross the ocean is to sail north or south until you catch one of these and then ride it out to a fairly predicable destination. At least if the sailors know about them. 

 

But overall I get what your trying for. My concern was mostly with the probabilities and die mechanics. 

 

A somewhat different take would be to limit the error to each day/week/or months sailing. Then one failure wont hurt as much. SO if you were handling it per day, and a ship could travel, say 100 miles in a day, then the worse result (double fumble) would only be a 100 mile error, and not 4000 miles!

I was thinking of Bart Roberts ability to land near just about wherever he wanted to as far as the accuracy goes, hence the Luck roll. . Of course that was latter and with better equipment, but even so, he once ended up only 2 miles from where he was aiming at. 

 

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Googles Bart Roberts...ok so still before the solving of Longitude (just) so a good example of what could be done even before John Harrison.

Without a history of playing Magic World and a few years since I even played RQ I’m a little out of my depth. Hence my need to get more eyes on it. I’ll keep tinkering. To my mind finding and riding those currents is part of the navigation roll. 

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6 hours ago, Coronoides said:

Googles Bart Roberts...ok so still before the solving of Longitude (just) so a good example of what could be done even before John Harrison.

Yes, it wasn't quite hopeless. Generally after a whil;e, they had enough knowledge to get an idea of where they were and to get to where they were headed, eventually. But there was a lot of stuff that could go wrong, such as the weather. 

6 hours ago, Coronoides said:

Without a history of playing Magic World and a few years since I even played RQ I’m a little out of my depth. Hence my need to get more eyes on it. I’ll keep tinkering.

 

Figure out what you believe the typical results should be the work the rolls and math to fit. For instance, I think most ships made it from point A to point B and that the big question was how long did it take. Some ships were lost but probably not the majority, or else there wouldn't have been any cross ocean shipping. The shippers would have went bankrupt. 

Weather played a factor, but could be minimized somewhat by avoiding sailing in certain times of year. 

It's not that being able to fix the longitude made long distance sea travel possible. It was possible. It just made it a lot safer.But if it hadn't been mostly safe to begin with then it wouldn't have reached the point where fixing longitude became important. Of course the ships themselves made a difference, and got better over time. Crossing the ocean in a sloop or brig was safer than doing in in a longship or pentakonter.

6 hours ago, Coronoides said:

To my mind finding and riding those currents is part of the navigation roll. 

If that's the case then once a navigation roll is successful and a navigator find a current it should be easier to stay in the current. In the age of sail that is precisely how ships got back and froth from Europe to the Caribbean. At least once they knew about those currents. So a ship would slot into the current and ride out out, and would reliably get from Point A to Point B, barring storms or enemy action.

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9 hours ago, Atgxtg said:

...

Figure out what you believe the typical results should be the work the rolls and math to fit. For instance, I think most ships made it from point A to point B and that the big question was how long did it take. Some ships were lost but probably not the majority, or else there wouldn't have been any cross ocean shipping. The shippers would have went bankrupt. 

...

If that's the case then once a navigation roll is successful and a navigator find a current it should be easier to stay in the current. In the age of sail that is precisely how ships got back and froth from Europe to the Caribbean. At least once they knew about those currents. So a ship would slot into the current and ride out out, and would reliably get from Point A to Point B, barring storms or enemy action.

Yes, normally for design project I have a pretty clear goal. This time I have become muddled by competing interests. Let me explain. When I get a new game the first thing I do is create a world to see what it can do. I have been doing this ‘off screen’ and trying to keep any house rules setting neutral.

When writing the house rules for ocean crossings I’ve been thinking about the historical people who did this regularly.

However, a premise of my world is that for a long time the isolationist Western Elves of the Elfland continent where the only ones who could make ocean crossings. However in the last decade of so a human culture has developed the Knorr and is struggling to make its first ocean crossings.

In other words I have just realised that one bit of my brain has been writing rules for when ocean crossings are commonplace while another bit of my brain wants them to be something only a few can achieve. The result is unclear goals.

Possible solution: If good charts exist to a destination showing prevailing winds and ocean currents etc. you need a navigation check to start and another to finish and even if you wont be too far off. If you don’t have access to good charts then it’s weekly checks and each failure takes you a % of the distance travelled that week off course. 

In some settings charts are commonplace and even part of a Navigators ‘trade tools’ as starting equipment. In other settings Charts are rare and acquiring them, if they exist, requires gold or adventure like acquiring a new spell.

In my Broken Isles setting the rare Western Elves can just buy charts in thier home continent. For everyone else charts are as rare as Grimoires and they need gold or adventure to prize them out of the hands of the Western Elves or they need to cross blind and then make thier own chart.   

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Ok the next iteration...

Seafaring
Crossing an open ocean like the Pacific or Atlantic is tricky business without a way to measure longitude and with the western Iron Age/medieval  ships provided in Magic World. The rules as printed are fine for island hopping and coast hugging but if you want to emulate Columbus or Leif Erikson then some house rules are needed.
Firstly, based on historical examples a seaworthiness of at least 22 is recommended and even then if the weather turns bad there is a good chance you will sink. It is a good idea to avoid storm season. Really big warships are not recommended because they lose seaworthiness to fast and  can't carry enough supplies to feed and water their large crews for the duration of the crossing. Secondly, recruit the best navigator you can, a good navigator not only prevents you from going off coarse but can also help avoid the worst weather and make use of currents and prevailing winds. 
House rule: Ocean Crossings
While within a day’s sail of the sight of land the usual navigation rules from the core book apply (MW135). When in the open ocean multiple Navigation rolls are needed and Luck plays a part as described below.  
When considering an ocean crossing the first question is do you have a detailed and accurate chart of a known route that makes use of ocean currents and prevailing winds? In some settings charts are freely available or at least a collection of them is included in a navigator’s starting equipment as ‘trade tools’. In other settings charts might be rare and hoarded secrets as difficult to acquires as grimoires of spells and just as valuable. Another possibility is that an accurate chart to your destination simply does not exist. Each chart is one way, a return journey would use different currents and winds. That said charts are often found in pairs describing a return journey.
Navigating with a chart
If you have a chart then you need only roll Navigation and the Navigator’s Luck for the first week away from land, for any week immediately after a Whole Gale or Hurricane (MW135), and the last week before you expect to see land. 
Navigating without a chart
Navigation and Luck rolls at sea are made once per week (or part thereof). 
Making the rolls
Out of sight of land longitude can only be figured by error-prone dead-reckoning so halve navigation skill. If out of sight of land and 3 or more days in the week have complete cloud cover then halve navigation skill again. Remember at sea effective navigation skill is never higher than the navigator’s sailing skill (MW42). If out of sight of land also roll Luck. At the end of the week the Chronicler makes all rolls secretly and tracks the ships actual position. Compare the results of the Luck and navigation rolls to the table below:
Navigation result    Fumble    Fail    Success    Special    Critical
Luck result                    
Fumble    70%    45%    20%    0%    0%
Fail    60%    35%    10%    0%    Fair Weather
Success    50%    25%    0%    Fair Weather    Fair weather, No encounter
Special    40%    15%    Fair Weather    Fair weather, No encounter    Fair Weather, no encounter, +10% speed
Critical    30%    5%    Fair weather No encounter    Fair Weather, no encounter, +10% speed    Fair weather, fortunate encounter, +10% speed.
Interpreting the table.
%: Figure the distance the ship has travelled that week and multiply by the %. This is how far off coarse the ship is. To determine the direction off-coarse roll a d6: 1 West, 2 East, 3-4 North, 5-6 South.
Fair Weather: next week the the ship will find itself in Light Winds (MW133-135).
No Encounter: the ship does not encounter any random encounters in the next week.
+10% Speed: the ship has made good time add 10% to the distance covered that week.
Fortunate Encounter: the ship experiences some good fortune. The Chronicler can invent an event or encounter. Examples include a downpour when the ship is low on fresh water, dolphins ride the bow wave increase the Luck of all aboard by 10% next week, when food is low a dense school of biting herring surround the ship, or they encounter another ship that is somehow helpful.

Making a chart.
Anyone with an eye for detail can copy an existing chart. To create a new chart first you have to make the journey without one and keep a log in a blank book (MW35). After you have reached your destination the Chronicler makes a Scribe roll for you to create your chart. Remember each chart is one way from a particular departure point to one destination. If the roll is a fail you are told your logs are insufficient to make a good chart. If the roll is a fumble you are told you are successful but anyone using the chart will arrive 100 miles from the destination. On a critical success add +10% to the Navigation roll of anyone using the chart.

Navigator Occupation
You are a necessary crew member of any ship able to navigate to all the trading ports. Your travels have shown you the known world and plenty of adventure but you long for more. Now you seek to find a voyage of exploration. When you discover new lands your name will be remembered forever.
Skills: Sailing, Swim, Navigate, Nature, World Lore, Scribe, one other skill as a personal speciality, and one weapon skill.

 

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The Hârn Pilot's Almanac has quite detailed rules for this sort of thing (navigation, shipboard roles, trade), and it's still available after all these years. It's worth a look if you want to drill down into seafaring.

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