vs Aggro: [Backstab], [SI:7 Agent], [Fan of Knives], [Bloodmage Thalnos].
vs Midrange/ Control: [Backstab], [SI:7 Agent], [Tomb Pillager], [Bloodmage Thalnos].
Good/Bad Match up:
vs Hyperaggro: Bad.
vs Aggro: Equal.
vs Midrange: Good.
vs Control: Good.
How does this deck works:
The finisher of this deck is the combo: [Leeroy Jenkins] + [Shadowstep] + [Leeroy Jenkins] + [Cold Blood] + [Cold Blood].
To achieve this combo you will need to play the [Gadgetzan Auctioneer] and a lot of spells. You will get some extras spells from [Xaril, Poisoned Mind] that will help you to recycle the cards of your deck until you can have them.
One of the difficulties to play this against Aggro or Hyperaggro decks is that you dont have much protections except the [Fan of Knives], so take care to know when to play it. With this kind of decision you will learn how to Master this deck.
The best synergy is to use [Conceal] on a [Gadgetzan Auctioneer] so you can use him to get lots of cards while you get some board control.
Another big one on this deck is to use [Edwin VanCleef] at the right moment. One good example is to use him really early in the game together [Backstab] + [The Coin] + [Edwin VanCleef].
This is the weak point of this deck, as you need all the cards. Maybe you could swap [Leeroy Jenkins] with [Reckless Rocketeer] (Cost one mana more and does one less damage) but there is less damage as together with 2 [Cold Blood] + [Eviscerate] is a total of 17 Damage with 10 manas.