How much can you melt with fireball

[S'mon]

In the Golden Age of Sail, many nations actually lined their ships with copper. This reduced plant growth on the hulls and protected the wood from worms. I recall reading that it was so effective that the French ships were able to outmaneuver the British navy and choose when and where to engage. Whether that would protect a ship against a fireball, I don't know.

The thing that would protect a ship versus fireball is gold. Ships are expensive and require a long time to build. If you have adventurers running around on the high seas, I bet that the local governments are going to offer a bounty on any captured ships they bring back with them. And if you sink that ship to the bottom of the ocean all your loot goes down with it.

Hmm ... I think I may have just hijacked my own thread....

What I saw running Classic D&D was that it made piracy inadvisable - an MU5 on the target ship could easily devastate the attacker. My son loved blowing up attackers with fireball. At one point a fleet of cannibals and pirates attacked - 8 ships. 2 rounds after entering spell range vs his ship, which had MU8, MU5 and MU4 aboard, 5 attacking ships had been wiped out and the remaining 3 were fleeing, having never got into attack range.

 

[Greenfield]

On a lake surface, a Fireball would melt up to a 40' circle of ice, up to six inches thick. (Yeah, I know I said 12 earlier, but I forgot about the "half damage to objects" rule.)

Then what? The lake, still being very cold, will start to ice over again in a few minutes. If the FB didn't melt all the way through the ice sheet then you have a big puddle, which will start to freeze again.

As for melting coins in a heap: I'd say it depends on the Hardness you assign to gold and silver. You might melt a shell over the top or the fluid might settle down deeper before it congeals. DM's call. definitely.

As for ships: Let's be honest, there are parts of the D&D fantasy where we just have to look the other way and pretend certain things don't exist.

Castles and walled cities make very little sense in a world where enemies can fly, become clouds of smoke or simply D-Door or T-Port inside. Teleport Circle would allow an enemy to march a sizable army right into the palace grounds. Yeah, it's 10k in material costs, but that's far less than the cost of an extended siege. And that's not even considering the obvious magical ways of breaching or destroying fortifications.

Similarly, as was pointed out, using ships in warfare is a losing proposition.

My solution to things like that, aside from the "Pay no attention to that man behind the curtain" approach, is to presume a foundation of spells designed to protect structures. Not very popular with adventuring characters, and thus not well documented in the books, these would be extended magical rituals (casting time of one day, minimum) that are simply part of the construction of anything you expect to see combat.

So Warships are protected from magical fire, Warp Wood, and so forth. It's only the more common merchant fleet that need concern themselves with that sort of thing.

So, in my world, when you see a construction that appears to be of exceptional quality and beauty (i.e. "master worked"), there's a good chance it has some protections embedded.

This makes me think another thread is due.

 

[Celebrim]

So Warships are protected from magical fire, Warp Wood, and so forth. It's only the more common merchant fleet that need concern themselves with that sort of thing.

This is the stat block for the ship the PC's have been on for the past 35 game days, while journeying to the Isle of Dread.

“Valiant” - 20 Engine Corvette
Colossal Object
Hull: AC: 8, Hardness: 10; Masts: AC 14, Hardness: 14; Rigging; AC 2, Hardness 0 (Energy Resistance (Fire) 2, non-magical flames do not spread)
Hit Points: 800 hull, 150 masts, 210 rigging
Move: Sail - 15 (normal wind)

Length: 110 feet
Beam: 27 feet
Draught: 15 feet
Weight: 400 tons
Crew: 105 (20 sailors, 5 officers, 60 gunners, 20 marines)

Engines
2 Ballista (Aft)
2 Ballista (Fore)
2 Light Mangonnel, 6 Ballista (Broadside)
4 Maulers on pivot mounts

Stats For Ballista
Maulers: Crew 2, Accuracy -1; Penetration +2; Rate of Fire ½; Damage 2d6+3; Range Increment: 80
Ballista: Crew 3; Accuracy -2; Penetration +4; Rate of Fire 1/3; Damage 2d6+6; Range Increment: 120
Light Mangonnel: Crew 4: Accuracy -3; Penetration +6; Rate of Fire 1/3; Damage 4d4+6; Range Increment: 140

It's currently beat to heck, leaking, patched up, with a dismounted ballista, missing one mast and half of the other two, and pretty much out of spare sail cloth, but it's a pretty formidable boat when undamaged. In game, it's a medium warship. A few nations are currently fielding flagships equivalent to roughly 18th century 4th rate SOL's, with a 22 engine broadside that is murderous to anything approaching the ship from the side. Most warships have a complement of mounted riders that serve as scouts or screens against aerial attack, in addition to a considerable number of archers. Such warships don't look much anything like 12th century cogs or galleys, but why would fantasy worlds with dragons and magic exactly emulate all the features of the 12th century? Nonetheless, because a 12th century Edwardian castle ruin doesn't look like it would be of much defense against an aerial attack or an invisible intruder (why would it?), doesn't mean that castles are ships of the setting are obsolete.

 

[Greenfield]

On the subject of Hardness: Since D&D doesn't give actual hardness for many materials, I thought I'd look up a fe on the Mohs scale.

There is enough overlap with the chart in the DMG to let us relate the two tables.

Hardness Substance or mineral
0.2–0.3 caesium, rubidium
0.5–0.6 lithium, sodium, potassium
1 talc
1.5 gallium, strontium, indium, tin, barium, thallium, lead, graphite, ice[12]
2 hexagonal boron nitride,[13] calcium, selenium, cadmium, sulfur, tellurium, bismuth, gypsum
2.5–3 gold, silver, aluminium, zinc, lanthanum, cerium, Jet (lignite)
3 calcite, copper, arsenic, antimony, thorium, dentin
3.5 platinum
4 fluorite, iron, nickel
4–4.5 steel
5 apatite (tooth enamel), zirconium, palladium, obsidian (volcanic glass)
5.5 beryllium, molybdenum, hafnium, glass, cobalt
6 orthoclase, titanium, manganese, germanium, niobium, rhodium, uranium
6–7 fused quartz, iron pyrite, silicon, ruthenium, iridium, tantalum, opal, peridot, tanzanite
7 osmium, quartz, rhenium, vanadium
7.5–8 emerald, hardened steel, tungsten, spinel
8 topaz, cubic zirconia
8.5 chrysoberyl, chromium, silicon nitride, tantalum carbide
9 corundum, tungsten carbide
9–9.5 silicon carbide (carborundum), titanium carbide
9.5–10 boron, boron nitride, rhenium diboride, stishovite, titanium diboride
10 diamond, carbonado
>10 nanocrystalline diamond (hyperdiamond, ultrahard fullerite)

Compare this to the Hardness table in the DMG/SRD:

Substance Hardness Hit Points
Paper or cloth ......... 0 2/inch of thickness
Rope ...................... 0 2/inch of thickness
Glass ....................... 1 1/inch of thickness
Ice .......................... 0 3/inch of thickness
Leather or hide ........ 2 5/inch of thickness
Wood or darkwood . 5 10/inch of thickness
Alchemical silver ....... 8 10/inch of thickness
Dragonhide ............ 10 10/inch of thickness
Stone ...................... 8 15/inch of thickness
Mundane crystal ...... 8 25/inch of thickness
Iron, steel, or deep crystal 10 30/inch of thickness
Mithral .................... 15 30/inch of thickness
Adamantine ............ 20 40/inch of thickness

Iron and Steel have a Mohs Hardness of 4 to 4.5, and a D&D scale of 10.

Crystal (such as fused quartz) has a Mohs Hardness of 6 to 7, and a D&D scale of 8.

Since one scale shows steel harder than quartz, and the other shows it being softer, I think we can safely say that any relationship between the D&D hardness scale and reality is coincidence.

Even so, we could use the relative hardness of gold and copper to steel on the Mohs scale to suggest that pore copper has a Hardness of about 6, and Gold at 4 or 5. We can rate pure silver the same as gold.