Random Thoughts: The Average Unicorn's Magic

Late last night, as I was attempting to fall asleep, I got to thinking about Sparkle's magical ability.  I had been rereading her character bio earlier in the evening, and I began to wonder if giving her 8 different spells to use was a bit OP, considering her magical strength is less than that of an average unicorn, who've pretty much only been shown to use Levitation and Illumination spells, with the occasional 1 or 2 extra spells for special situations.  But then, a thought occurred to me:

What if a unicorn's magical strength didn't limit the number of spells they could use, but instead the power of said spells?

In the show, it is implied that each unicorn has a set magical capacity: that they can only use so much magic.  In season 1, Spike and Twilight have a short conversation about how normal unicorns only have a little magic to match their special talent.  A lot of people tend to assume that this means unicorns can only learn a certain number of spells.  But the more I thought about it, the less sense that assumption made.  After all, in the show there are plenty of unicorns that study magic, and there are plenty of spells to be learned.  If most unicorns could only use a select few spells, why bother documenting spells in books that could be found in public libraries for all to read?  

If you think about it, anypony could pick up one of those spell books and learn the contents within, even an Earth Pony.  But an Earth Pony couldn't perform any of the spells they had bothered to learn.  I would like to propose that it works the same way for unicorns: any unicorn could study and learn any spell, but depending on their magical capacity, they may or may not be able to perform that spell.  Each spell has a certain difficulty level: A spell such as telekinesis is incredibly easy: anyone can do it.  But a spell such as teleportation is incredibly difficult, and requires a lot of magical energy to perform.  To some degree, this unspoken rule of spell difficulty is seen in the show.  In the episode Sonic Rainboom, Twilight mentions that the spell she uses to create wings for Rarity is incredibly difficult to perform, and it is shown to leave her a bit drained after performing it once.  

Going a little bit more into hypothesis territory here, I'd also like to propose that a unicorn's cutie mark can actually make some spells easier to perform.  Referring back to Spike and Twilight's conversation about unicorns having magic related to their special talents, I began to think about why unicorns would only have a little magic related to her special talent.  I came up with the idea that a unicorn's cutie mark worked a bit like a special skill in RPGs: depending on the unicorn's talent, any spells related to that talent would be easier for that pony to perform.  For example, say a unicorn's talent is in singing: any sound-based spells or spells related to voice alteration would be easier for that unicorn to perform.  Spells that may ordinarily be too difficult for a regular unicorn to perform, would come a bit easier to a pony whose talent matched the use of the spell.  That would also explain why ponies like Twilight, who's talent is magic in general, seems to be able to perform nearly any spell with ease.  Because her special talent is the art of magic itself, all spells naturally come easier to her.

So, knowing all of this, we return to the question I suspect most of you have lingering in your minds right now: if all of this is true, how come nearly every unicorn we see outside of Twilight and Starlight seem to only use two spells?  Well, based on what we've learned today, my theory is this: it's not that most unicorns can't use more than a few spells, it's that they choose not to learn more than a few spells.  Every unicorn has the magical capacity to use an unlimited number of spells: but most don't bother to memorize more than levitation, illumination, and perhaps a spell or two to help with their talent.  Beyond that, if they need a spell for a specific situation, they can simply look it up in a book, perform it once, and then forget about it.  The number of spells a unicorn knows is entirely dependent on them: a unicorn with weaker magic can still know more spells than a unicorn with average magic, if they choose to dedicate the time to learning those spells.

Hopefully this little ramble of mine helped to clear up some things about unicorn magic.  If you've got your own theories about how magic works in Equestria, feel free to post them in the comments!  I always love hearing other people's ideas about things like this.  Thanks very much for reading, and have a wonderful day!