As recounted by Christopher Nitz, former Senior Prepress Systems Analyst at WOTC, in the CGC article, creating test prints was expensive for WOTC
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It can retrieve energy cards that have been discarded or used during the game
At ~$94 per box, it remains one of the strongest High Class Pack investments in the SV era
Playing the deck, Ive found enough times to notice that doing this with creatures can be a little awkward-bouncing them on command is one thing, but having to bounce more than one during each upkeep can get onerous
Then you can spend six mana ad nauseum to make a 1/1 Soldier creature copy of any artifact you control, like the aforementioned Spine of Ish Sah or Mycosynth Wellspring or even just a Sol Ring or Gilded Lotus