Hi,
It's not good enough in control v control, or in control v aggro, and it's too good in aggro v control. It's being used exclusively to silence taunts, and because of the odd/even dynamic and because of Spiteful Summoner, it no longer has the downside of being attached to an understatted minion. These decks are actively looking for stuff to put in their decks and the 2 silence minions don't have enough downside in these kind of decks.
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Medical Explainer