On Sea Monsters

What is a sea monster? Why is it so horrible? and how do I avoid just letting my players hack it to death?

There are three notable features of a sea monster. First, its aquatic nature. Second, its predatory savagery. Third, its immense girth. For some reason tales of sea monster result in totally massive creatures more often than purely land based tales.

On Bulk

So just how big is it? This is one of the biggest questions when making your sea monster. A great place to start out is "how big is the boat?" Sea monsters are rarely compared to the size of a person: they are compared to the size of the boat. Some sea monsters will attack the people on a vessel much larger (but those tend to be fish people and tangential to our real topic), and sometimes you throw a monster against the ship that's much smaller than it, but as a general rule, the boat and the monster should be evenly matched in size. This is especially true of monsters you want to drag the ship down.

One of the monsters shown is an appropriate encounter. The others? Not so much

Gurps suggests adding HP and ST in accordance with the cube of weight. This is the scientificly correct way to do things, due to something called the square cube law. Of course, most giant monsters are flagrant offenders of the square cube law, and so I (and many others) suggest raising ST with the cube for most giant monsters. A third option is to use the damage from Cubic Strength and the HP from Square ST: this will give monsters that require lots of hacking away at but don't kill ships with a single blow.

The table below matches stats to sizes, with three entries for each SM. Note that individual monsters are likely to vary from the numbers given. Not that it really matters if a ST 120 monster hits your boat or a ST 125. The examples given to the side are conservative weights: Record holders, Boasting Anglers, and Film directors usually move the creature up a level or two, when they don't create another creature that looks like the original but is much bigger.

Weight	SM	Short Length	Long Length	Cube ST		Square ST
100 lbs	0	1.5m	2.1m	ST 9	0d+2	ST 8.5	0d+1
150 lbs	0	1.7m	2.4m	ST 10	0d+2	ST 10	0d+2
200 lbs	0	1.8m	2.7m	ST 11	1d+-1	ST 12	1d+-1
300 lbs	1	2.1m	3.1m	ST 13	1d+0	ST 15	1d+1
500 lbs	1	2.5m	3.7m	ST 15	1d+1	ST 19	2d+-1
700 lbs	1	2.8m	4.1m	ST 17	1d+2	ST 22	2d+0
1000 lbs	2	3.1m	4.6m	ST 19	2d+-1	ST 27	3d+-1	Big Bottlenose
1500 lbs	2	3.6m	5.3m	ST 22	2d+0	ST 33	3d+2
1 tons	2	4m	5.8m	ST 24	2d+1	ST 38	4d+0	Record Squid
1.5 tons	3	4.5m	6.6m	ST 28	3d+-1	ST 47	5d+1
2 tons	3	5m	7.3m	ST 31	3d+1	ST 54	6d+0	Great White
3 tons	3	5.7m	8.4m	ST 35	4d+-1	ST 66	7d+2	Orca
5 tons	4	6.8m	9.9m	ST 42	4d+2	ST 85	9d+2	Mausosaur
7 tons	4	7.6m	11m	ST 47	5d+1	ST 100	11d+0
10 tons	4	8.6m	12m	ST 53	6d+0	ST 120	13d+0
15 tons	5	9.8m	14m	ST 60	7d-1	ST 150	16d+0
20 tons	5	11m	16m	ST 67	7d+2	ST 170	18d+0
30 tons	5	12m	18m	ST 76	8d+2	ST 210	22d+0	Humpback
50 tons	6	15m	21m	ST 90	10d+0	ST 270	28d+0	Moby Dick
70 tons	6	16m	24m	ST 100	11d+0	ST 320	33d+0	Megaladon
100 tons	6	18m	27m	ST 110	12d+0	ST 380	39d+0
150 tons	7	21m	31m	ST 130	14d+0	ST 470	48d+0	Blue Whale
200 tons	7	23m	34m	ST 140	15d+0	ST 540	55d+0
300 tons	7	27m	39m	ST 160	17d+0	ST 660	67d+0	Kraken
500 tons	8	31m	46m	ST 190	20d+0	ST 850	86d+0
700 tons	8	35m	51m	ST 220	23d+0	ST 1000	101d+0
1000 tons	8	40m	58m	ST 240	25d+0	ST 1200	121d+0
1500 tons	9	45m	66m	ST 280	29d+0	ST 1500	151d+0
2000 tons	9	50m	73m	ST 310	32d+0	ST 1700	171d+0
3000 tons	9	57m	84m	ST 350	36d+0	ST 2100	211d+0
5000 tons	10	68m	99m	ST 420	43d+0	ST 2700	271d+0
7000 tons	10	76m	110m	ST 470	48d+0	ST 3200	321d+0

Bulk is a defense in and of itself. Even if a creature has no natural armor, large animals can take a lot of damage by the simple fact that their vital organs are deep within them. Even an animal without natural armor should have DR at 1/10th of its HP. Additionally, targeting the vitals of such a creature is not trivial. Those wishing to target the heart, brain, or kidneys will need either a lot of penetration from their missile or a  sufficiently ridiculous stick to put a blade on. Adding another DR at 1/10th to attacks vs the vitals is appropriate.

On Aquatics

 One of the trickiest difficulties of a sea monster is that its in the water and you're stuck on a boat -- if you're lucky. Being alone in the water is even worse, unless you have some powerful technology or magic to back you up. Don't let the characters attack the monster whenever they feel like it, and most attacks can't be blocked or parried.

Sea monsters are generally more maneuverable than ships. They may also be faster, but that's true less often -- though you may have to run with the wind to outrun the thing. Most of the time, you don't go to the sea monster: the sea monster comes to you.

The water often forms an additional barrier against injuring the creature. The diffraction in the water gives a -4 to hitting something across the water barrier. Not a problem if you're a aiming for the main body, but if you're aiming for a place that you can actually hurt the thing, like an eye, it can be tricky element to add. And if launch the weapon in the water itself your arm will be impeded! Ranged weapons have greatly reduced ranges, and firearm projectiles will actually bounce off of water.

nothing visible underwater

Of course, That's once you spot the thing. The water forms a reflective barrier that makes it near impossible to see things far away. The angle is important.. you actually have a chance to see things coming up from under you -- but the distance is very reduced. Most of the time, you have to rely on spotting momentary surfacing  (which is usually not complete) or bubbles coming up from a surface creature. Fortunately, most of the time you just want the monster to go a way, and a lot are pretty obliging about displaying before they attack or coming to you to latch strait onto your ship. But exceptions do exist, particularly among leviathans, and a smart monster can use hit and run to great effect.

If you're serious about running a fight in the water, gurps pyramid 26 -underwater adventures, contains the rules for underwater fights.

On Being Monstrous

There are a number of shapes that show up in sea monster lore again and again.  The serpent, the kraken, and the leviathan (ie, really big fish shaped creature). There is a curious dearth of arthropods, probably because arthropods aren't open water creatures and don't get as big as the others.

Sea Serpents tend to be smaller than the ship. They also tend to either have main bodies impervious to most hand weapons, or to display only their head during an attack. 

One signature mark of the sea serpent is the head. Unlike the other two classic forms, The serpent can stick his ugly head up on board the ship and look you in the eye before he eats you. The head of a serpent moves across the deck of the ship monstrously fast -- it should have enough reach that it can strike most of the crew with them striking it. Attacking the serpents head requires ranged weapons, a sufficiently long stick, or acrobatics in the rigging.

The other signature of the sea serpent are its coils. In fiction, sea serpents are always coiling around the ships they attack. Their goal may be to crush the ship, it may be to drag it under, or it may be to just get a firm grip on the thing its attacking (which would actually a tactically sound idea if it was dealing with a leviathan).

The Kraken is a squid shaped monster. That is to say, it has lots of arms. It is common for fiction to not even bother giving a proper count on the arms. Battles with Krakens on the big screen often depict a lot of tentacle chopping. Realistically, this will end the battle pretty quickly -- unless you have the kraken with the improper arm count or a cinematic kraken. Of course, its usually only heroes who can cut through a tentacle. Be sure you know a kraken's goals -- If its trying to just grab the crew for a quick snack, it can be terrifying as it sweeps around tentacles, grabs three or four of them, and then disappears into the deep. Of course, Krakens in fiction usually try to sink the ship, presumably because they want to eat it.

The leviathan is at once the tamest and the trickiest of the forms. Its the truest to life, as evidenced by classics like Moby Dick (Ok, Jaws can also be considered a leviathan). A battle with a leviathan is a very impersonal thing. There is no eye contact, and the leviathan makes good use of the protection of the sea -- most attacks can be made without leaving the water. Of course, Leviathans don't usually float right under the boat and chew until their is a hole: Leviathan combat is about movement. They charge their targets, and its not uncommon for them to launch themselves right out of the air after an attack.

And sometimes the craziest monsters combine multiple forms. Such is fiction, nightmares, and crazy GMs. When I was a kid I gave a serpent a tentacled end, a shark head, and crab claws. When you do this, step back, and ask yourself what the thing is going to behave like. In retrospect, the thing acted much like a serpent -- a personal, face to face conflict based on picking off specific crew. So when you run into something really crazy, just ask yourself what it acts like. And its entirely possible for that kind of crazy monster to act like different monsters at different times.

There is actually a fourth archetype that may play into some sea monsters: the Dragon. which deserves its own article (and got its own book). In some ways, its an extension of the personal and armored serpent, but in other ways, its an extension of a land dwelling monster to the ocean. A similar thing can be said about the giant crab -- essentially a land monster in an aquatic environment.

Facing Down a Ship

A sea monster attacking a ship generally has one of three goals:

• It wants to eat the ship
• It wants to drive the ship out of its territory
• It wants to eat the people

These motivations effect the way the monster fights.

It also important to remember that most monsters are dumb brutes that don't realize the advantages they have. The smart ones generally only have a few tricks that make them one step above animalistic, and don't tend to come up with new tricks. Of course, truly intelligent monsters are possible. Just don't be surprised when they become much tougher to defeat. 

Dragging it down:

So often in fiction, the goal of the monster appears to drag the ship down into the water with it. Ships are remarkably buoyant, up until the point where they start taking water on the inside. It takes a great deal of strength to drag the ship all the way down, but merely tipping the ship over can be just as bad. Of course, most boats are built to intentionally be difficult to capsize. In most cases, the crew can do little to help the ship beyond clever tricks to give small penalties to the contest (likely -2 at the most), and fighting off the monster.

To drag down a ship, a monster needs a way to grasp it -- so serpents and krakens tend to do this the most. The point at which the monster grips the ship is important, as that's where the heroes need to focus their attack.

Ships are remarkably buoyant and stable -- those are pretty much the qualities they are designed for. They also won't fight back being tipped over with more than brute force -- which means you need a reasonable way to roll strength. B349 has rules on how to adjust the scores. You can resolves a monster trying to tip over or pull down a ship however you want, but remember the following:

• Treating it as a grapple where sinking is a take-down takes a mere 1 second
• Treating it as a grapple where tipping or pulling down is a pin will still be over within 10 seconds.
• Ships are big. Even a monster capable of simply pulling it down will need time to move the ship the requisite distance.
•  Attempting to pull a ship down is a great way to cause it damage. 
• Attempting to pull down a ship may result in inadvertent tipping. 
• The time to capsize is effectively a time bomb for your players -- it forces them to confront and defeat the monster quickly. Time the capsize accordingly

This is completely made up, but the following should be playable.

• Find the effective strengths of the ship and the monster. 
• Each round roll a contest of strength.
• Each margin of success by the monster sinks/tips the ship by 5%.
• If the ship is being pulled down, it returns to its place at a rate of 10% per margin of success. Its also appropriate to add the ships stability to this roll -- and to tip the ship if the stability bonus gives the ship the victory. Don't add the two numbers together -- track them seperately
• Once 100% is reached, a tipped ship is on its side, and starts taking on water. It takes 5 minutes of work and a successful shiphandling roll at -4 (this may be a good place for a technique) to right the ship. The monster may attempt to just keep rolling the ship, which doesn't really change its
• Once 100% is reached on a ship being pulled down, the ship starts taking on water. It keeps on resisting the monster's pull, though as water fills the ship, it will resist less and less. 

Is this a tip or a pull under?

The rate at which water enters the ship is highly dependent on the design of the ship -- the GM should decide on a rate.This method can and should be modified when need be -- changing the rates at which the contests of strength happen and 'percent capsized' can slow, speed up, or make more swingy the rate at which the boat goes down. Smaller boats should tip or pull down faster than large ones.

Sometimes a Leviathan will attempt to capsize a vessel (classically a smaller boat). This is not an attempt to drag down or tip the ship via grappling rules. The leviathan needs either a large ST advantage or persistence and a clever mind to pull this off. Model a single attempt like a fluke sending a wave or bumping the ship with the head as a take down attempt using half the ST score. A more involved attempt like amplifying the rocking motion of the boat takes longer (probably 20 seconds), but may be able to use the full ST score at the GM's option. Unlike a physical grapple, these actions DO give the crew a chance to react and fight back, but they will need to be aware of what's going on and ready to counter it to avoid massive (-4?) penalties to their rolls.

Breaking the Ship:

Leaks can happen through punching through the hull, but they can also happen due to internal stress. And sea monsters don't generally punch small holes in the ship: they squeeze it, ram it, or otherwise attack the grand structure. Monsters generally don't bite ships -- boats they might, but not ships. 

Despite the cannon ball problem  and the fact I often have problems with how slam and constricting damage work, this is probably one time when the rules on those three topics come out nicely. Alternatively, have the ship make HT rolls after each slam or 5 seconds of constriction or take an appropriate amount (10 percent?) of damage. Its worth noting that most underwater ramming attacks will take place with fairly long intervals as the creature rams, pulls away, and then builds up speed again. Impact velocity for leviathans is generally between moves 10 and 15. Additional DR should be given to a creature that intentionally rams, and especially one thats designed to do so (Orcas come to mind).

Using Sea Monsters

The sea monster fight is interesting because its almost obligatory to throw in once and boring to do it twice. Voyage of the Dawn Treader -- many monsters, only one serpent. 20 Thousand Leagues Under the Sea -- one giant squid. Dreamwork's Sinbad: Legend of the Seven Seas. Several different monsters, but only one counts as a sea monster as treated in this work. In Odysseus, we have two sea monsters-- who show up at the exact same time. Order of the Stick talks about fighting every aquatic monster in the book (literally, as befits order of the stick), but so far only ever shows one fight with a big aquatic monster (a summoned giant squid). There is a lot of precedence for fighting a giant monster once and only once. And if the campaign (or campaign leg) consists of nothing but fighting massive aquatic beasts, you run the risk of being boring.

Unless! your characters go into the game knowing that sea monsters are main foe and specialize as hunters of them. A crew of larger than life whalers hunting down killers that ravage shipping lanes, or  hunters of exotic creatures. This is because sea monsters by nature don't bring a lot of plot with them. They show up, terrorize a ship, and then go away. Additionally, it takes an odd set of skills to fight a monster correctly and most characters won't have that set.

But lots and lots of campaigns can use sea monsters as an added element. I hope this article gives you lots of ideas of what to add and how to handle the fight.