Wow, I thought the thread was about to die, and y'all bust out with some excellent thoughts. Lemme try out the multiquote feature.
The PCs can shine by blowing up ships left right and centre (mind you, if 4 ships spontaneously explode during a battle, that's probably not going to be entirely paradox free...) and then have to get serious to deal with the one warded ship. Or alternately they may be so tied up with the magic-wielding ship that they don't have time to properly deal with the minion ships...
This is a possibility. I was also thinking about the fact that pirates aren't interested in destroying ships so much as in capturing ships, and the obvious ways of dominating a sea-battle as a mage tend to involve sinking ships to the bottom of the sea. So maybe they're just really, really good at the defensive arts: no pirate-hunter will be able to touch them.
Still, I like the idea that sea battles (especially the first few) should be exciting, dramatic scenes. If one player can end the first sea battle through the careful application of their spheres, it'd be a ludicrous letdown.
Part of the question is how prevalent Mages are in your universe. If 1 in 1000 ships has a magically-capable crew, then there will be very few anti-magic counter-measures in place. If, on the other hand, there's a reasonable expectation that any given pirate ship, privateer, or other hostile force will have a magically-capable individual on the crew, then there will be a variety of magical countermeasures in common use.
My plan, previous to this, was to have the PCs be among the first (if not the very first) piratical cabal in the Caribbean, and have a major impact thereby. Your list of countermeasures, however, is so awesome that I'm having to rethink this plan.
There will certainly be other spellcasters in the area. Mexico is still held by the Aztecs, whose magic is staggeringly epic but limited to the mainland. Haiti is held by some mysterious group of former slaves, having held their revolution a century early and without the benefit of the American or French Revolutions first; they're doing their best to monopolize the slave trade in the Caribbean. The Order of Reason (precursors to the Technocracy) have a few explorers in the area, part of an effort to define the New World scientifically and bring it under their sway, but so far they don't have any real permanent power. And there will be the odd practitioner here and there.
I might take your countermeasures and introduce them shortly after word of the first few PC victories reaches shore. It'd be a great backhanded compliment to the PCs' influence.
I may be way off-base with what you want from your game here, but how wedded to the Mage:SC implied setting are you? Is the game more "Mage:SC set in the Caribbean with pirates!" or is it "Caribbean pirate fantasy which just happens to be run using the M:SC rules"?
I've played in a gameday one-shot game with this type of scenario that used the
Ars Magica ruleset (one of the Atlas editions) with great success.
Ars Magica was actually my first choice, because I'm definitely just jonesing for the idea of wizards in the golden age of piracy. But god love 'em, the rules for Ars Magica just make my eyes glaze over; they're way too intense for me right now.
humble minion said:
You say that you want a mage to be roughly equivalent to a cannon. I'm not sure how literal you mean that. Do you want them hanging in the rigging, hurling broadsides of fireballs at the enemy ships? Cos that's not how Mage in my experience have gone. Mage has, for me, always been about applying minimum amounts of sneaky force to achieve the desired objective. And that CAN come across to some players and/or DMs as overly-methodical not-fun God-style play, particularly if they rock up to a game expecting swashbuckling Pirates of the Caribbean style action and end up with ... something very different. Mage - particularly when played in its most *efficent* manner by very results-oriented PCs/players - doesn't really do swashbuckle. Swashbuckle is dramatic, and daring, and risky, and spectacular. Mages tend to try really hard to avoid all of those things.
First, I was thinking about the "equivalent to a cannon" thing, and I've changed my mind. I'd kind of like each point of arete to be roughly equivalent to half a dozen cannons. But we're not talking purely about blasting, here; rather, I'm talking about relative strength of ships. Sea battles, in my research (by which I mean watching Master and Commander and reading the Temeraire novels), aren't won in a single firing of cannons; generally it takes several broadsides before one ship strikes its colors. I want PCs to be very effective in battles, but I want it to take a few rounds of back-and-forth before the battle is won (or lost).
As for mages being subtle, Sorcerer's Crusade doesn't have coincidental magic. Rather, there's casual magic, which is magic operating according to a magical tradition that the local rubes believe in. Hermetic magic in England is casual, but is vulgar in China, whereas casting the i Ching would be the opposite. The PCs won't need to be subtle, as long as they can persuade their pirate cohorts not to kill them as devil-worshippers (which is a much bigger threat among the general populace than it is among pirates, natch). Of course, the flashier they are, the faster their reputation will spread, for good or ill.
This just made me think...
Ninja vs. Pirates!
Players in Mage almost always operate like ninja, using trickery, subterfuge, and the expert application of minimum force. Swashbuckling is kind of the opposite, showy and explicit.
As for the level of swash that I expect to be buckled, we're not talking Johnny Depp, unless my players really go wild. I'm more thinking
On Stranger Tides,
Master and Commander,
Temeraire, etc.
Thanks again, folks! I might open another thread asking about specific plot/character ideas, given the wonderful thoughts here.