This deck aims to win on turn 7 or at the latest turn 10 with a OTK combo. It is incredibly consistent in doing so with an extremely fast draw engine, while also having ample removal and heals to survive.
If you have Wretched Tiller, one Deathspeaker, and a Hysteria in hand you can do a smaller version of the full combo. Play Wretched Tiller, then play Deathspeaker to make him immune. Then play Hysteria on Wretched Tiller. To calculate how much damage it does, you need to multiply 2 by the health of all minions that will be on the board when you do the combo, not including Wretched Tiller itself. On an empty board this will deal 8 damage because Deathspeaker has 4 health. So you need the opponent to have 11 health spread across their minions on the board in order for this combo to do 30 damage to them. It turns out many decks will indeed have more than that on turn 7 even if you fully cleared their board the turn prior (if you are preparing to do this combo sometimes it's better to not fully clear it on the previous turn). So this deck actually wins on turn 7 with this combo pretty consistently.
You can do even more damage on turns 8 or 9 even if your opponent hasn't played many high health minions. You can play some of your own minions to add to the damage total, Doomsayer is especially good for this as if you play Doomsayer before the combo it will deal an extra 14 damage to your opponent.
Sometimes you need to dump removals and other cards from hand without getting maximum value from them so that you can have hand space to be able to draw more. You want to keep some removals against aggro but generally try to draw as fast as possible.