While not as experienced as other big-name Hearthstone players, Ostkaka earned his place at the top of our list because of his recent triumph at the 2015 World Championship. Using Oil Rogue, Grim Patron Wrarrio, and Freeze Mage decks, Ostkaka took first place in the Championship and earned his first major victory (and a $100k reward).
This is quite the accomplishment considering the fierce competition. Ostkaka managed to beat Hearthstone veteran, ThijsNL; which was a surprise to many. Below is small clip that demonstrates Ostkaka's quick thinking and ability to create unique strategies.
Prior to the Championship, Ostkaka had little tournament experience so he is still new to the pro scene. He is definitely a player to look out for in future competitions.