MArcomage

Mountain unicorn, Rare, Legend, Runic, 12/12/12
Attack: 30
Wall: +20
Quarry: +1

Well, it's been a while since this card was introduced. It somehow managed to have more plays than any other rare including durable ones and stay on top for a long time. Why? I'll explain.
First of all, it is both offensive and defensive, and both these aspects are very decent. 30 attack, up to 30 wall and up to 10 tower - getting all these effects is like playing two good uncommons at once. But there is also a third uncommon - Mountain unicorn gives +1 Quarry. With these effects Legend keyword looks just like a little cherry on the cake - nothing more.
But all those things would be balanced - it's a rare, after all, it's meant to be powerful - if this card wasn't so easy to play. 12/12/12 cost definitely can't be called "prohibitive".
All these factors make Mountain unicorn a good addition to almost any deck, from rushing to turtling. Versatility is power, and this card is one of the most versatile in whole pool.
I'd say its cost should be raised to 17/17/17, or one of its aspects should be nerfed (attack from 30 to 15-20?).

Ooh, how did I miss this one? It should be in my Unliving deck.

I have neither used it nor seen it used, but I have to admit that it looks pretty potent currently.

It's a good all-arounder card, but not one that you would say it affects the game greatly (because it's a little from everything). It's not a one-shot, nor a game changer as other powerful rares are.

Increasing it's cost by 15 resources would be quite harsh.
Reducing it's attack to 20 seems more reasonable, or it's cost might be changed to require 2 resourcces but higher numbers (e.g. 20 bricks, 20 recruits).

I agree, It should be nerfed.
Anyway the statics are showing a strange ranking. Absorption is the second common and cursed amulet is the second uncommon; I don't know how old they are (7 years? more?) but it's the first time I see them so high in the chart. Just to say that the statistics shouldn't be totally trusted if we talking about nerfing cards.
But yes, this Unicorn should cost more or have a smaller attack.

Of course. Top played cards can also be "flavor of the month", like Absorption. Or specific cards like Princess of elves - this card also looks good in every deck, but it makes good things for game as a whole.