They play creatures with enters-the-battlefield triggers because they like getting the value there, and they like getting that value again
(6/6/2025) "Flashback [cost]" means "You may cast this card from your graveyard if the resulting spell is an instant or sorcery spell by paying [cost] rather than paying its mana cost" and "If the flashback cost was paid, exile this card instead of putting it anywhere else any time it would leave the stack." (6/6/2025) You must still follow any timing restrictions and permissions, including those based on the card's type
Even though this deck is a Transmute test deck, it is also a test deck for Ravnica block cards
#5 Spelunking Set: The Lost Caverns of Ixalan Market Price: $4.02 Spelunking is a fairly costed ramp spell that also draws a card, and offers insane combo potential with any cards that put lands into play tapped like Arboreal Grazer and Scapeshift
You might need to make sure you have Sol Ring, Snow-Covered Wastes or Thran Dynamo on the field to cast Kozilek, the Great Distortion since you need colorless mana
Card info Defile editions Decks with Defile