<Snipped quote by Feisty-Pants>
Well heres the thing. Why isn't there a way to protect from those 'forbidden spells' like in almost every other magic based lore? My problem is just how... inconsistent... the potter universe is with its spell lore. And going back to the start, there is no 'cost' to casting a spell. You could just spit out death ones back to back like a machine gun and not feel any ill effects until you just got tired of flicking your arm. And well, spells used for plot convenience even though they clearly contradict previous lore and lots of fun little inconsistencies and that stuff which confuses me and lots and lots of logic gaps and everything.
One example of a logic gap is that there is that liquid luck potion that does scary phenomenal things, and you can make this thing in your back yard. Why isn't that just made, stockpiled, and turned into pills or something, and/or why don't people just make this stuff and everything? And what makes it so that you can't make a spell that does the same thing, why does it have to be a potion? Basic things like that are what I'm confused about if that makes sense.
1. Because there's really just not much to protect against it. If the wizard is stronger than you, or has a stronger will, and your spells clash...you lose. Sad to say. (The only difference is Harry Potter, and how he got lucky with the protection of his Mother.) The lack of a cost is what it is, but it's just how the system works. That being said killing people (Avada Kedavra) has been known to take a toll on the soul of the caster. (Not tossing further information out to cause spoilers or anything of the sort)
2. I'm under the presumption that Liquid Luck, while it is extremely useful, is either lawbound to restrict the amount you can make because of its effects. Or it's extremely hard to make due to the rarity of the components required to concoct it. You can't make a spell of it simply because you can't, or the spell hasn't been created yet, and at that point it would only have one use so you'd have to keep recasting it. (Sounds relatively impractical)