Sinking a Rowboat - How?

Rechan · Sep 23, 2007

I posted this over on the Rules forum, but it was suggested to go here, so I thought I'd give it a shot.

Here's the situation.

The PCs are traveling about three hundred feet from a ship to the beach. They are in a rowboat.

Half way to shore, the boat is attacked from below by a monster who is stupid enough to think the boat is a big fish. I want the monster to punch a big enough hole in the boat to make the boat start taking water.

A rowboat is 8-12 feet long, made of wood. Wood has a hardness of 5 and 10 HP/Inch. I figure a rowboat's bottom is 1.5-2 inches of wood (So maybe 15-20 HP?).

Any rules suggestions on simulating 'boat is taking water'? How much damage should it do to accomplish this, how many rounds do you think it'll take for the boat to have taken enough water to be submerged, any mechanic suggestions for 'bailing water out' (or how many rounds that will save them), etc?

Way I figure it, the PCs will take one of two routes: Bail out the water/row and keep the monster at bay, OR stay in one spot and try to destroy it where they stand. So I want to be prepared for either action.

Primitive Screwhead · Sep 23, 2007

I have a book called 'Broadsides', a D20 book that covers naval engagements. Heres how they would handle that.

Your hitpoints are right on the money, a Fishing Boat is listed with a Hull of 15 hps, hardness 6, break DC of 26.

If the vessel takes more than 50% {7 points} of hull damage, it starts taking on water based on how damaged the hull is, counted in 'water damage' which acts like subdual damage. Once the lost hitpoints + water damage exceeds the Hull hit points, the vessel starts to sink.

Characters can bail out 1 point of water damage per round.
Characters can also patch the Hull, with a Profession Sailer or Craft: Boat check DC 15. This provides a DR of 1 versus water damage.

For this vessel, the following list shows how much water pours in each round:

Code:

Hull HP left   Water Points Taken   What happens when it sinks
  7                      1
  6                      2                Floats for 2D6 rounds, then sinks
  5                      4                      
  4                      6                 Floats for 1D6 rounds, then sinks
  3                     10          
  2                     15                 Floats for 1D3 rounds, then sinks
  1                     30
  0                                          Total Wreckage, non salvable

When sinking, the vessel drops 25' per round.

Needless to say, a rowboat taking on water is not a good thing

A Large Shark would need to take two solid bites {1D8+4}, but a Huge Shark could shred the boat {2D6+7} in a single *CHOMP*

If I were running it, I would have the boat knocked down to 6 hit points, which allows for the players to make choices one way or the other.

I hope this helps!

Rechan · Sep 23, 2007

That helps a lot, thanks! How many rounds do you think it would take to get to shore? The boat is listed at 1 1/2 mph, but that's not helpful on a round by round basis.

To give you a good idea of what I'm after, I'm probably going to use something like a modified Grick. Up the tentacle damage, reduce the DR, give it more HP so it doesn't have a glass jaw. The stats for the monster is a little eh tho.

IF I were to use the Grick, then it throwing around four tentacle attacks at the hull, I imagine a combined effort should let it punch through the hull.

Primitive Screwhead · Sep 23, 2007

A Cog, the smallest vessel in the book, runs at a speed of 7 under sail and 3 under oars. A Rowboat, having less oars, should be slightly slower than that... so a speed of 2... which translates in tactical combat maps to about 10' per move action...

Assuming calm water, winds, and no current. If you are coming in on the tide, you can add in 5 to 10' of movement due to the tide.

Since this is an older boat, I would go with two characters needed to row... add a little bit more tension into it

Felnar · Sep 24, 2007

taking on water would slow a boat, which could heighten the tension

Mark Chance · Sep 24, 2007

Felnar said:
taking on water would slow a boat, which could heighten the tension

So would a kraken. Use a kraken in addition to the slow leak. Now that's tense!

Primitive Screwhead · Sep 24, 2007

You could also go for the 'tearing the ship apart' problem. As mentioned above the Break DC of the rowboat would be 26.. so your alt.Grick could grab on, make a minor hole in the boat.. then hang on and try to rip it in half...

Maybe thats a bit too much tho