Vorthosy How-does-magic-work Question: In your mind, is Planeswalker magic a different kind of magic than clerics, wizards, druids, and such who are not Planeswalkers, or just different in scale? Does every plane have its own rules for magic (and other existential things) or are they all sharing a common rulebook (if-you-will)? Are there different kinds of planeswalkers, do you think (different sorts of sparks)? Have you ever played Mage: The Ascension?
This is Brandon canon, not official MTG canon. I've always imagined that growing up with the mana all around them in MTG planes that almost everyone has some kind of little, innate magical gift that you wouldn't really call a spell. More powerful ones manifest in dramatic ways. But you can also learn to do more with study, becoming a wizard or the like. I do imagine that every plane has some slightly different tweaks of physics, and metaphysics.
I think there are probably different kinds of planeswalkers and sparks, but again, this is my instinct--not official canon. Here, I'm just a fan talking about how he sees the game.
I have played Mage, and like most White Wolf games, I found the experience to be very fun--but reading the sourcebooks tends to be even better.