Mulligans
Surprisingly effective and can surprise many players. The deck consists of Shuffle synergies, card draw and removal.
Ideal curve is: turn 3 Elekk, turn 4 Portal Keeper (or Shadow of Death if opponent has some moderate minion already) into turn 5 Stowaway.
Prime Shadow of Death targets in your deck are Waxadred or Zilliax. Apart from those, it can be used to shuffle useful minions from your opponent (i.e. 8/8s from shaman’s galakrond, big dragons, etc.). Against more aggresive decks, don’t be afraid to shuffle mediocre minions since tempo provided by Stowaway is still huge.