Overview
The main issues combo decks have is its strict requirements, being overall weak until the combo, and no win condition without the combo. All of which are solved with this deck.
A Miracle Rogue with your standard Gadgetzan Auctioneer and cheap spells, but instead of using Academic Espionage to prevent fatigue, you preform a combo after emptying out your deck. The combo is to summon potentially 5 Leeroy Jenkins after emptying your deck for 30 damage (depending on how you execute the combo). This combo can be executed in a number of ways, making it more flexible than other decks, and is why I think this will be more than just a fun gimmicky deck.
Combo Gathering
Cards to keep in hand: Wondrous Wand, Togwaggle's Scheme, Leeroy Jenkins, Myra's Unstable Element.
Optional Cards: Shadowstep, Preparation, Cold Blood
Cycle through your deck using the numerous draw mechanics including Gadgetzan Auctioneer, in order to obtain the necessary combo pieces. You can play Heistbaron Togwaggle whenever is convenient because you only need Wondrous Wand obtained through his discover battlecry.
Combo Execution
Once all combo pieces are in your hand play Myra's Unstable Element because you want your deck to be empty. Then play Leeroy Jenkins and use Togwaggle's Scheme to shuffle many copies into your empty deck, guaranteeing your next draws will be only Leeroy. Then play Wondrous Wand to draw 3 Leeroys that cost 0.
Combo Variations
You can play your Leeroy earlier in the game and use Shadowstep to lower the cost when preforming the setup turn for the combo. You can also use Preparation to lower the cost of any of the spells cast during the combo. Another aspect is you can use Cold Blood to give a Leeroy additional damage. You will usually need 1 turn of setup in order to get the full 30 damage but often times you don’t need 30 to kill your opponent.