best starter deck pokemon trading card game gameboy for Game Boy Official Nintendo Player's Guide from Nintendo Power: Nintendo Power: 0045496691790 Books Start Deck 100 Battle Collection

I believe that we can glean a hint of the answer in Mark Rosewater's latest State of Design article, from July this year

It's an answer to answers - commonly run in decks to answer removal that's targeted like Swords to Plowshares or Beast Within or mass like Blasphemous Act or Damnation

(They each put the top card of their library into their graveyard.) Legendary Creature - Human Knight Drain (CTRL to add secondary) Draw Braids, Arisen Nightmare At the beginning of your end step, you may sacrifice an artifact, creature, enchantment, land, or planeswalker

Herald's Horn and Heirloom Blade may seem innocuous, but every future tribal deck can play them