
It is said to me that a potion that normally enhances your attacks with extra dice (or Spell too I suppose, see "Courage") would not make a Crossbow bolt stronger. Why not?
"Because" they will reason, "the magic potion just makes your muscles temporarily stronger. So it might make you throw a dagger or hand axe harder than before, just as it would make you swing your Battle Axe or Sword Stronger, and do a more powerful hit to the enemy."
"But" they will say, "the Crossbow always is loaded in a specific way, you are not adding any extra tension to the bow string and you are just pressing the trigger like you would without supernaturally enhanced strength. So it shouldn't do any more damage."
To me though this is just an excuse to nerf the crossbow (again, what is it with people wanting to nerf the Crossbow? and often it's the same people who also believe it should be able to hit the close diagonals like a longsword; no offense to these people of course, I'm just puzzled by the logic)...
The game mechanic isn't based on historical accuracy, the laws of physics or any other sort of "realism" it's simply a game bonus is how I treat it. It makes your attack stronger because it does, that's the whole point of it. Calling it "Potion of Strength" doesn't mean it makes your arm muscles bigger. It refers to the strength of the attack (more dice = stronger, obviously, because it can do more damage, being harder to block completely).
What would a magic potion or spell that makes attacks stronger do for a Crossbow? You could say it magically focuses your aim, so that you are more likely to hit your target. Maybe you are more likely to hit the chink in the armor, or hit a vital organ. Or maybe it adds poison to the tips of the arrows or gives them better armor piercing heads? Maybe the spell never made you physically stronger, but made the weapon better, by increasing the weight of it (or the opposite, making it lighter and easier to handle) or sharpened the blade (or hardened it)?
See, using your imagination you can come up with a rationalization after the fact for why it makes a Crossbow attack stronger just as it makes the other types of hits stronger. Maybe it isn't referring to your muscle strength so much as the strength of the attack.
So to someone who doesn't want to nerf the crossbow this way, you haven't convinced me with your magic doesn't make you a better marksman argument. How does potion of defense work? Does it make your skin thicker? Does it nullify the trauma of the incoming attacks? Does it make your attacker more likely to miss? Does it make you move faster so you are more likely to dodge or block their incoming attacks? I'd tend to go with the last one. But this is magic we're talking about... somehow it works, and your justification for it working comes after the fact. I'm not against people changing the game, just challenging some of the commonly used arguments for why their way is better.
There are plenty of ways to make the Crossbow less powerful, but to me the Crossbow is fun to use and nerfing it only serves to discourage its use. Why would you want to discourage people from using it? If you as Zargon think it makes the game too easy for the heroes, there are other things you can do besides nerfing it. For example...
Make your monsters stronger or more numerous. Give your monsters crossbows too. Adjust the price. Whatever. But "nerfing" to me takes the fun out of it. Making a random chance for the string to break (making your weapon useless), or requiring you to spend more money on buying extra bolts (how many do you actually need per adventure? 20? 100? 1000?) or limiting the range to something silly like 9 squares (okay, so you haven't really weakened it for most encounters... you'll still be able to hit every monster in the room from the safety of the doorway, you just won't be able to shoot monsters on the other side of the long corridor without moving halfway there so within pursuit distance of the Orc and goblin). Sorry for the rant, but there you go. If you want to Nerf the crossbow go for it, but arguing the logic of magic physics to do it doesn't convince me.