Ruunin, the Relentless

Hi, i’d like to say that playing against this legendary is totally unbalanced. If you dont have a card to transform it, you have to face the same creature again and again. I killed it 4 times and the opponent brought to battle a 6/6 monster with 0 faeria. Dont you think this is imba? Unbalanced at least?

Neither, unless you get it with a cost-reduction (Bloomsprite, Aurora’s Creation, Ruunin’s Messenger).
That card is slow. Really slow.

Look at here to see how to counter it.