Zendikar is one of the most mana-rich lands in the Multiverse, and the set included several important milestones: land-based mechanics like landfall, the completion of the fetch land cycle introduced in Onslaught , and the inclusion of full-art basic lands in a major expansion set
Even unique error cards are coveted, with some selling for thousands of dollars
If you can find ways to untap and tap Sanwell multiple times, like with Puppet Strings, you can keep the card advantage flowing
If youre only after a specific card, it might be more cost-effective to just buy that single from an online store, a local game shop, or from someone who has it in their stock
You can also steal things from other players with Macabre Mockery or Gruesome Encore
Inevitable Defeat Inevitable Defeat, besides being uncounterable, sits in a region between Anguished Unmaking and Utter End, and should be a Mardu staple in EDH, at least