While the premium collector boosters guarantee at least 5 rares , play boosters have at most 4 rares, thus the price difference
Everything is just so cool
"Destroy" effects are far from the most reliable removal in a format like Modern, but there's a lot to be said for any card that replaces itself, especially at this cheap a cost
This is because some cards are rare and in high demand
If your deck is consistently trying to close the game out before the lategame (turns 7-9) and includes multiple tutors, game-changers, extra turn effects, or land restriction effects in it, theres a good chance your deck is an Optimized one
Sure, Yargle and Multani only have six toughness and will die to basically any removal spell that's not direct damage, but who cares