Crossovers with differing magic systems

[RandomPasserby]

We all know that crossovers are great fun. But what do you do when the two fandoms you want to cross over have completely differing magic systems which will leave either the HP character hopelessly over or under powered compared to the rest of the characters.

And then some idiot gave me a crossover bunny. A crossover bunny for one of the crossovers I've always been a little leery of - actually entirely because of this topic - Harry Potter/LOTR crossovers. (For ease, I'm using LOTR to cover The Silmarillion, LOTR, The Hobbit, the HOME books and Tolkien's letters)

Good magic in Arda is limited to Istari, Maiar and the occasional (and usually exceptional) elf; everything else seems to fall under the umbrella of sorcery/necromancy and is therefore bad and usually to do with Sauron or Melkor. The only real human we see who is attributed any sort of magical power they weren't born into is The Mouth of Sauron (descibed as a Black Numenorean who learned great sorcery from Sauron) although there are mentions of spells created by Elves, Men and Orcs and an odd line which attributes some magical toy making abilities on the Dwarves (and a line from The Hobbit which gives them the ability to cast spells). Elves also have various abilites which appear magical but aren't, although the extend of those is unknown (as is their accessability to the average Onóno, Turotulco and Corintur*)

There are instances of magic similar to that of the HP universe. Finrod Felagund shapeshifts and has a magic song battle with Sauron, Luthien Tinuviel sang an enchantment to send Morgoth to sleep, Aragorn exhibits a nigh-supernatural ability to heal, Elrond has some control over the river around Rivendell and Gandalf has the most in common with the HP universe (being able to create, compel, disguise himself and cast spells). Most of these have at least some connection to the Maiar - the one with the least is actually Finrod who still grew up in Valinor (Luthien being half-Maiar, Aragorn and Elrond are both of Luthien's lineage and Gandalf is, of course, a Maiar himself) which still ties back to the Vala which ties back to Iluvatar. So most of the magic system of LOTR is based on the ability coming from (in some sense at least) Iluvatar, unless you happen to be a man trying it anyway in which case it's sorcery and evil.

The magic of the HP universe requires little exceptionality apart from an accident of birth - you can be a deeply unexceptional and rather poor wizard, something I can't recall happening in LOTR. HP magic is also more immediate, Gandalf says that a shutting spell on a door would take some time to do rightly which isn't true of the HP universe. We don't know what the longest canon spell is in HP but (from what I remember) spells in LOTR involve a lot of time and a lot of singing.

So how do you combine these two in a way that doesn't render the HP characters hideously overpowered (I loathe the 'why didn't they just fly on the eagles to Mount Doom' but substituting the eagles for a Firebolt doesn't inspire the same amount of loathing)?

* Tom, Dick and Harry to those of you unfamiliar with Quenya

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Obviously this is also an issue with other fandoms with contradictory magical systems although I'm having trouble thinking of any right now.

I suppose this depends partially on the type of crossover (discounting fusions).

1. The ever popular 'dumped in *other world* during the series' - the question of not only will their magic work but can they pick up some of the magic of the other world?
2. The 'dumped in *other world* pre-series and raised in *other world*' - this is more to do with the perception of their magic as well as what they are taught, could a witch or wizard learn other forms of magic by dint of having magical potential?
3. Reborn/reincarnated as *character from other world* - can they access their previous life's magical ability (along with memories and possibly personality aspects)?

It also depends on how powerful you want to make the HP character - especially in the cases of 2. and 3. (or 1. if they've lost their wand) - in canon a wandless wizard is somewhat helpless but fanfic has given various characters wandless abilites Voldemort would be envious of. This is somewhat more understandable in a 2. or 3. crossover since they will presumably be growing up without being told they need a wand and wandless abilities may strengthen.

Anyway, comments and ideas (and recs of any particularly good crossovers with otherwise contradictory magic systems) are necessary (and it doesn't have to be LOTR based either).

[physicssquid]

There's one fandom that has a fairly different magic system to HP, and that's the Inheritance Cycle, though there are some minor similarities. I.e. needing words of some sort for casting magic, dragons, dwarves, races that are seemingly typically associated with certain types of magic.

The main differences that I can think of, off the top of my head, are the fact that the Riders, Elves and others who can perform magic, don't need wands, many are capable of doing great things just by singing, and the fact that they seem to get as tired by using magic to do something, as they would if they'd simply done it with their bare hands.

There are, I'm sure, many others, probably including, Percy Jackson, though I haven't actually read any of those books. I have read other books that feature magic, like the Dragonmaster trilogy by Chris Bunch, which really does have a very different magic system to HP, but since I've not found any Dragonmaster fanfics, I'm guessing there aren't any, especially if Chris Bunch decided he didn't want fans writing fics about his characters.