As we learn what mechanics the set wants to care about, we preserve the flavor so that players can still point at a card and say, "Yeah, that feels like this character." But during this first phase of Magic: The Gathering | Marvel's Spider-Man 's design, we didn't need to worry about that
Mirari's Wake is also great because it isn't just a mana ramp card, it also gives all your creatures a minor buff, making it great for Selesnya token decks
To put it in perspective: Mega Blaziken EXs Mega Burning attack dishes out 120 DMG
In the long run, you can dump big creatures for almost no cost
Alternatively, go back to basics and learn how to play Magic: The Gathering, or how to build a Magic: The Gathering deck.
The sweetest thing about the card is how much it screams efficient engine enabler to my old-school eyes, though untapping all your creatures whenever you cast a spell is a pretty insane effect to have access to, especially as it comes with some neat additional benefits