Not only can you pester your opponents by forcing them to discard cards every turn, but once they're out of cards you have a creature that punishes them for their lack of cards in hand
Yes, it's repeatable and can also target items or locations as well
Extensive range covering every MTG product type, with competitive pricing and frequent sales
This allowed players to draft Rush of Knowledge quite highly, and splash it into many decks that otherwise wouldn't have had blue
It gives a tapped out player the ability to win counter wars, to redirect an ill-timed card-drawing spell, and generally plays havoc with the targets on the board
It's so much more than an overpriced tutor, because a turn-two Starfield ShepherdStarfield Shepherd can grant you either the land drop you need or a nice one-drop that can impact the board right away, like Esper SentinelEsper Sentinel or MockingbirdMockingbird