Appearing in over 696,000 decks in the format, the demand for this card is absolutely obscene, and its easy to see why
I will, however, remind you, that the card will essentially read "whenever you cast a spell, draw two cards", which does seem quite good
Adding or removing loyalty is part of the cost to activate the ability, not the effect itself
They're usually created when a permanent enters or as an additional effect of a spell, similar to the way Clue tokens, Food tokens, decayed Zombies, and Treasure tokens are created by other cards
Head Designer Mark Rosewater wished Magic had started with a spell card type and added instants, sorceries, and interrupts as subtypes, like how auras are a subtype of enchantment
Not quite a changeling is the full-party of Tajuru Paragon that literally says it counts as five total creature types