Edit: Evidently I don't know how this forum works. I'll just leave my *totally impractical* solution here, though:
Kingdom: Oracle, Procession, Baron, Fortress, Catacombs, Graverobber, Mint, Nobles, Border Village, KC
Open Procession/Oracle.
Turn 3: Draw Procession, Oracle and 3 coppers, processing the oracle into a fortress, discarding 2 estates and drawing 4 coppers. Buy a KC.
Turn 4: Draw Estate, KC Procession Fortress Copper. KC Procession Fortress 3 times, drawing 6 coppers, gaining 2 graverobbers and a Catacombs. Buy a KC.
Turn 5: Draw KC, KC, Catacombs and the 2 estates left in the draw pile. Play KC KC Cata, drawing 2 graverobbers, a fortress, 7 coppers, and discarding 2 estates. The draw pile contains 1 estate. Use the 2nd and 3rd KCs on graverobbers, remodeling the fortress 6 times, into 1 nobles, 1 border village-nobles, 1 procession, 1 Catacombs, 1 baron, and a fortress. Buy a mint, trashing all the coppers.
Turn 6: Draw Crossroads, Procession, a Catacombs, and a Nobles. Play fortress, drawing the Baron. Procession the Catacombs, drawing KC, KC, Baron, the 3 estates, and the other procession, gaining Procession and a Baron off a Border Village. Draw a KC off the fortress. You now have KC, KC, Baron, 3xEstate, Procession, Nobles. Play KC KC Baron, discarding the estates, then Procession, processing first the nobles (drawing the Catacombs, a Graverobber, the second Nobles, the second Baron, the second Procession, and the mint, gaining KC), then the Catacombs (drawing the KC, the second Graverobber, and the estates, gaining Baron and Border Village, gaining Procession), then the Graverobber (rescuing the Nobles and the Catacombs, gaining Nobles). We can then repeat this (rescuing Graverobber/Catacombs instead of Nobles/Catacombs) until the KC/Nobles/Procession piles run out, by which we will have played KC barons 8 times.