The objective of this deck is to control the board until you have the lightning hero power. Then use Fencing Coach to make your hero power cost 0 next time you use it. Emperor Thaurissan your hand so you have a 4 mana Clockwork Automaton, and a hopefully fully upgraded Sapphire Spellstone. Next turn, you have a 10 mana, deal 32 damage combo.
I have played this deck 4 times, and I have successfully pulled off the combo each time. Here are screenshots of it working.