Kelya Fendrul is the best for me thinking about only the stats buff, because comparing with Tarsa, Obsidian, General Sloam and Thaddius Brood, the shield is the differencial that makes an advantage, however we could say that the Obsidian is a counter of Kelya, and my consideration was that a tanker with magical resistence like Baakjira could make it halve the difference more than others cards could to revert a disvantage from one summoner to another that counters it.
!PIZZA