Black Foil - White Cross Filler Card: Population 2
Key Cards for Ardenn: Colossus Hammer - +10/+10 without worrying about the heavy equip cost is absurd
You can get away with only sleeving the scenarios, hero cards, and then only the cards in active decks that works well
You're also getting multiple popular Black cards that are essential for other Black control decks
I remember getting in line, a ChannelFireball pro got in behind me, and they had something like 300 cards
They are also oftentimes seen in other Urzas Saga or Cascade decks as well, as Urzas Saga is sacrificed on the third chapter allowing a Fast Land to enter the battlefield untapped even as a fourth land drop, and three mana is enough to cast Violent Outburst, Shardless Agent and the like