Three Hearthstone cards are to be nerfed by Blizzard to improve the much-maligned Boomsday Project meta. The cards involved are Giggling Inventor, Mana Wyrm and Aviana.
Giggling Inventor will have its Mana cost increased from five to seven. Note that the odd Mana cost that's been preserved will ensure it stays out of Even decks empowered by Genn Greymane.
The card is described by Blizzard as being one of the most powerful and popular cards ever created for the game, with no downsides to prevent players making room for it. It's hoped that Giggling Inventor will take some of the power out of Quest Rogue in particular.
Next up is Mana Wyrm, which will now cost two Mana instead of one. In recent sets the developer have moved away from creating powerful one Mana drops, as they can quickly run out of control if not removed promptly. It's hoped this will give players more time to react to the Wyrm, and before it can be empowered to an unhealthy degree. The deck most affect by the change is Tempo Mage.
Finally, Aviana will cost 10 Mana instead of nine. This will prevent the card being played with Kun the Forgotten King on the same turn, unless the player has access to cards like Innervate or The Coin. Notably, it will prevent Juicy Psychmelon drawing both of these cards in one go.
The release time for the balance patch has yet to be confirmed, but it will be released on 18th October 2018.