VoldeDON'TSAYTHATNAME - Flipendo :( Ah well, Tria isn't that much stronger than Duo anyway. It shouldn't be too hard as RPGs come, but there is a LOT of stuff to consider, considering the relative freedom the game gives you.
Wow, this could actually end up being a very interesting run o_O Levelling up also fully heals you IIRC, so this can be abused as can death warping, now that I think about it. They can be useful both ways I'm pretty sure spells level based purely on how many times you use them, so you could either pummel enemies that are weak to a spell when levelling or find one that's immune and just cast it enough times. Weaknesses of regular enemies will also need testing, since they didn't put in an identification spell until the second game. VoldeDON'TSAYTHATNAME - Flipendo Ah well, Tria isn't that much stronger than Duo anyway.
The golem thing you fight in the TV when Peeves hexes you - VermiliousÄevil's Snare - Verdimilous/Incendio (pretty obvious, since Hermione basically tells you) Anyways, some weaknesses I remember off-hand: Kudos if you actually do this, because I have always wondered what the hell Strength affects in an entirely magic-based game (except for the very end of the second one, where you fight with the sword). The only way to test this will be to equip certain gear and see how much more damage you do/how much less you take. I have little idea of how the battle mechanics in this game work, aside from Agility which is obvious and that the Flipendo spells get much stronger at higher levels (.which you won't be reaching). Making/finding a record of all the hidden items will also help because there are TONS, as well as the secret passageways, which save lots of walking time (some are only one-way though). It will also be worth checking out whether or not the petrification spells work in important battles (I think Mucus Ad Nauseam always works but it's expensive as heck), as well as Wingardium Leviosa which only works on "light" enemies.
Grinding I think will be needed in certain parts, simply to do enough damage (for example, Verdimilious Duo is basically mandatory for taking on the troll in the bathrooms), although card combinations can overcome this to a degree I remember some being pretty powerful, especially at low levels, or having some very useful effects. The save anywhere feature is always a huge help in a segmented run, especially in this game where saving doesn't take that long.
I haven't actually played it in forever but I remember it being reasonably challenging and overall a good lot of fun, especially for a movie tie-in, and I thought it was great that it came out on GBC at the time because I hadn't gotten a GBA yet >_>
I was thinking of doing a Youtube emulator run of this at some point because it would NEVER get enough verifiers (I think Chamber of Secrets for PC was stuck in verification for over a year or something), but there we go.