The most expensive cards are almost always ultra-limited print run pieces: 39 Pikachu Illustrators, 7 Super Secret Battles, 2 Blastoise Presentations
Additionally, a standard deck box typically holds around 60 to 80 cards, making it perfect for tournament play
Sword of Truth and Justice lets you do this every time a creature deals combat damage
This one never saw the bannings that Tolarian Academy did and is still used to great effect in Legacy, Vintage and Commander (if you can afford its 500 price tag)
You break the symmetry of these board wipes by casting them in situations where you're going to lose less permanents than your opponents, making the board wipe favorable for you
A 2/4 with lifelink is also nothing to sneeze at, making Mangaras slightly higher mana value a bit more palatable than itd be on a less relevant body