Hearthpwn

It will cast twice if you have completed the questline for a minimum of 9 cost minions. 

This card is going to be crazy strong. Late game summoning 7 and 8 drops for 3 mana. That fact its discover means you normally get something very useful. 

So you need it to be 5 cost or more to really get above average value out of it, considering a choice of three random four cost minions probably gets you an ok 4 cost.

That means playing 4 overload cards before this, which means you're probably not playing it early on.  It kind of works as a late game value card if control Shaman existed.

What will happen when it is upgraded?

Summon more minions?

i assume cost of the minion is increased

yesterday was the theorycraft and i saw how a streamer use it and believe me its really strong and fun xd