The older a card is the less chance there is that it will be underrated
Load your deck with white creatures that dont have vigilance, so they can swing and stay tappedyou can add creatures with Vigilance but be aware: those creatures become lightning rods for your opponents removal
So, before you start rummaging through some old cards and think to yourself, "Ah, yes, this old card has a black symbol, surely it must be a common, and I can slot it right into my Pauper deck." No
They were expensive because they were only printed once, in Eventide
As Jake notes, Players cant realistically use a lot of their expensive Standard cards in other formats because their power level fades compared to many cards from supplemental sets
Instead of burning through life points, it attacks the minderasing your opponents library one card at a time