On the Upcoming Hearthstone Balance Changes for Hearthstone, the card Yogg-Saron, Hope’s End totally loses it's value, meaning and fun, because his nerf will make his effect stop if he is no longer there or if he is silenced.
The full nerf of it says:
"This is the most controversial card we've ever made. Some people LOVE Yogg, and others hate it. We felt like seeing Yogg in tournaments was not where we originally hoped it would end up. Yogg should be for players who want to have a lot of fun, but maybe not the card you see frequently in high-level tournaments. Yogg is relatively weak in power level for nearly every class at every level, but is slightly above average in 2 decks – Tempo Mage and Token Druid. We didn't want to nerf it so much that it couldn't still be a fun card for players who currently love Yogg. Yogg-Saron will now stop casting spells if, during Yogg-Saron’s battlecry, it is destroyed, silenced, transformed, or returned to its owner’s hand. We tried a bunch of things and we think this is a significant enough nerf that it could reduce the amount it gets seen (especially in tournaments), while still maintaining the dream for people who love the card.
In addition to the above changes, we will be addressing the bug where cards with Overload cast by Yogg-Saron, Hope’s End will not causeOverload to the player in a future update."

The full article can be reat at: http://www.hearthpwn.com/news/1756-upcoming-hearthstone-balance-changes-shaman-hunter