That said, I can understand why Wizards of the Coast was careful about introducing these types of cards to the game
Sadly, prices have bounced back slightly since then
Transmute Artifact can effectively trade up any artifact, even a token, for literally anything else in your deck, making it a widely sought-after card for any artifact deck looking to splurge a bit
$0.49 Stillness in Motion Tarkir: Dragonstorm $0.99 Death Begets Life Tarkir: Dragonstorm $0.35 Snarling Gorehound Murders at Karlov Manor $2.49 Will of the Sultai Tarkir: Dragonstorm Commander Decks $0.99 Multani, Yavimaya's Avatar Edge of Eternities Commander Decks $0.49 Lluwen, Imperfect Naturalist Lorwyn Eclipsed $1.49 Skull Prophet Tarkir: Dragonstorm Commander Decks $0.39 Molt Tender Aetherdrift $2.29 Summon: Titan Final Fantasy $0.35 Midnight Tilling Lorwyn Eclipsed $0.35 Town Greeter Final Fantasy $0.35 Drag to the Roots Duskmourn: House of Horror 0 results found
Then there are cards like Unexpected Assistance that turn blockers into card and mana advantage
Worst case, you could stage an Invasion of Arcavios