You would get very powerful effects at an efficient mana cost in exchange for giving your opponent a fair warning and the chance to play around the telegraphed effect
(Targeting opponents, anything they control, and/or cards in their graveyards is a crime.) Draw two cards
Perhaps this is why this card was available (reprinted) and included in nearly every Core Set
Many force their opponents to mill their decks, hoping to bin some of their best cards - or force the player to lose the game by running out of cards to draw
Rush of Knowledge (Onslaught/Legions/Scourge) The common consensus in Onslaught/Legions/Scourge draft was that you wouldn't want to play a deck with more than two colors, since there weren't many cards which allowed you to "mana fix" - that is, fetch a third color of mana
For any MTG player cracking a pack and wondering why the card they pulled doesnt seem to belong to the current set, The List is responsible