All you have to do is follow this tips:
*1st round : SKIP !!!!! (Why? Because enemy plays 1st round 2 pawn's. Your pawn will have 1/4. It's weak minion, in this heroic you must beat him fast).
*2nd round : Play ONE White Pawn. (Why? Read 3rd round).
*3rd round : Play THREE White Pawns. (You will have right now 4 pawns, one from previous round versus 3 enemy pawns. It's first advantage in this match).
*Always try to get double damage by keeping your board uneven (for example - 5 yours and 4 enemy).
*LEFT SIDE IS ONLY FOR MOST USELESS MINIONS (like White Pawn's) due to enemy's hero power.
*Think TWICE or more about every plays. Think about:
-Destroying his minion and don't expose your most valueable minions to death.
-Dealing his hero damage.
*USE HERO POWER!!!
Remember that you have only 15 cards instead of 30 enemy's. Trying to control him like in normal mode is equal to death by fatigue. You have to take board presence 4rd turn. After 4rd round will be probably too late. If your enemy get's advantage after 5 round, press restart button.
If enemy will use his hero power 2nd turn - literally nothing to do here.
I beat him in my 1st try using this tips.
That's all. If you are lucky you can get lethal in 7-8 rounds. Enjoy!