With the quest and a 1 or 2-drop (unless you get Crystology, which is a must keep) during the mulligan, it's not hard to complete the quest by turn 5 or 6 most games. Then you drop the Mechano-Egg or Mechanical Whelp to be copied and begin board domination. Be careful not to commit to the board too much if fighting a priest as Plague of Death will ruin your day without a reload. For a video with a 100% winrate (just 3 games) against Embiggen Druid, Resurrect Priest, and Big Spell Mage, check out the following video: https://youtu.be/Btv1Tk9GoJg