Almost a sweep it was. Except for the duel with 
What do you think who has won?
Yes, I thought so too. Then, in the final stages ... I was one magic card short and it turned out to be
Congratulations, my friend!
Still, it was a "six wins out of seven matches" quest.
Then I decided to invest my DEC into the Basic Mystery Potion.
I pulled the chest open and ...
Two rares and an epic. Is this the potion's doing? Or is there some more mystery in store?