The more packs you open, the more likely you are to pull a rare card
Similar to the other planeswalker decks, each list wants to play its feature card quickly and then protect it until it can activate the third ability
Yavimaya Elder (Ext, S, Block) A mainstay of The Rock (a black-green deck that thrives off of card-advantage creatures), the Elder potentially nets you a four for one advantage: it can block and kill a creature, then sacrifice to draw a card plus two lands
Reanimator decks are looking to get a powerful creature into the graveyard quickly through discard or Entomb effects, then cast a spell to return it to the battlefield at a steep mana discount
You can be greedy with Kitt Kanto, using it to pump up one of your big attackers each combat, or you could give +2/+2 to an opponent's creature on their turn and goad it
Key also created all-or-nothing situations, because you can strand the Key without anything worth untapping