Based on the latest market prices tracked on TCG Stacked, a foil copy of All Will Be One is worth about $27.98 USD
If Falthis and Kediss are your commanders, your deck may contain cards with black and/or red in their color identity, but not cards with green, white, or blue
Once you have your engine going, you can focus on casting two copies of Time Warp or Exsanguinate
The lands aren't the only cards getting this treatment, either: each of the 20 possible Mythic Rare cards from the Phyrexia: All Will Be One Bundle: Compleat Edition can be found with this treatment
Cast-from-exile decks are inherently strong because their mechanics rely on drawing cards
This protection helps them stay on the board long enough to turn your small group of tokens into a large army