Kezan Mystic and Mad Scientist are like the yin and yang of secrets in HearthStone. One gives and the other takes. One is the question, the other is the answer. Both are incredibly powerful cards in the right situation, or the right deck. And together, they govern the use of secrets in the metagame.
Currently the world of secrets is largely in an acceptable balance. While Mad Scientist has granted them incredible potency, being virtually free in many cases, Kezan Mystic has appeared on the scene to at least partially bring them down to earth. Indeed, it’s probable that instead of nerfing Mad Scientist like Undertaker, Blizzard decided to introduce a Loatheb-like counter to secrets, represented in Kezan Mystic.
But the balance here, tied as it is between two very powerful cards, comes at the expense of future design decisions. Secrets are an interesting mechanic, one that goes beyond merely class-focused keywords like Overload or Freeze. They occupy a unique place on the game board where few things can reach them, and they interact with the opponent’s turn in a way nothing else can. It seems a natural evolution of the game that more, if not all, of the classes receive secrets. While Blizzard can certainly decide against doing so, for variability of play, this would be an unfortunate loss. Eventually HearthStone will need new mechanics. They add excitement and intrigue to new sets and decrease the predictability of play upon release. This is why new mechanics are central to every new major set of Magic: The Gathering. It would stand to reason that an expansion of secrets would come before exploring other options.
Unfortunately, Mad Scientist and Kezan Mystic would likely be too powerful in the event that more classes receive secrets, assuming that any new secrets go beyond Paladin levels of awfulness. There would be virtually no reason not to run Mad Scientist in any secret deck, as it offers nearly guaranteed value. Indeed, Mad Scientist has always had enormous value when it comes to secrets. Its deathrattle is the equivalent of a card draw and a gain of two or three mana, and its body is only one stat point below the vanilla test threshold, resulting in 4 to 5 mana of value for 2, and two cards for one.
Kezan Mystic too, can be a very powerful card, providing roughly 5 to 8 mana of value (depending on how you look at it) for 4 when used in the right situation. It’s balanced by the fact that it only effectively works when playing against two specific classes (sorry Paladin, you don’t count), and only when secrets are out, something a player can’t control. Therefore, it’s a highly meta-dependant counter, similar to Harrison Jones or Big Game Hunter. Indeed, many thought it was useless until the recent ladder domination of trap Hunters and Mech Mages running Mirror Entity (at one point, I ran two and didn’t regret it). But in a game where more classes have secrets, the drawback to Kezan Mystic begins to disappear.
And this becomes a problem when more decks and more classes have secrets. Games in which both sides have secrets and Kezan Mystics are often ping pong matches, with secrets moving back and forth, and the game resolved solely based on Kezan Mystic draws. But in a secret-heavy world, playing without Kezan Mystic means you risk being overpowered by the value of Mad Scientist. And thus a meta cycle is formed, with players trying to figure out how many decks run secrets to know how many Kezan Mystics to run, while players choose whether to play secrets based on how many Kezan Mystics they see.
Such a cycle is a normal part of any metagame. But the problem comes simply from how powerful the effects of these cards are in isolation. Brian Kibler recently wrote about the problems with Big Game Hunter as a counter, since it decreases the fun of big creatures. But Kezan Mystic’s effect is potentially stronger with respect to secrets; it doesn’t merely destroy, it steals. A Mage that plays Mirror Entity on turn three only to have it stolen by her opponent immediately after is usually in a perilous position unless she has a Kezan Mystic of her own.
And thus we can see the potential issues with more secrets, especially powerful ones. Four mana or higher secrets are out of the question due to Mad Scientist’s strength alone, and a Kezan Mystic stealing one would be game-winning. And if more classes obtain even two or three mana secrets, both Mad Scientist and Kezan Mystic are likely to reach the ubiquity of the already problematic Dr. Boom and Big Game Hunter dichotomy. Kezan Mystic would simply become one of the most used cards in the game, destroying the inherent fun of secrets, just like Big Game Hunter.
And this problem is exacerbated by the fact that nothing else interacts with secrets, except for the Hunter-specific card Flare. The fact that secrets are often powerful effects obtained nearly for free, while their sole counter is an enormous swing, creates a situation where a two card mini-meta decides wins and losses. Unfortunately, this has effectively ensured that future development in secrets will either be highly problematic, or will simply not happen, which are both unfortunate results. In the end, if Blizzard wants to expand secrets, they may be forced to nerf both cards, although I expect it is unlikely as they didn’t nerf Mad Scientist in the first place.
This all relates to the overall problem of countering a broken card with a hard counter: it’s a little like swallowing the spider to catch the fly. The problem simply becomes replaced by a new one. I do hope to see more secrets in the future, although I fear the dark dichotomy of the problem and its counter will keep the existing secret distribution firmly in place.