http://us.battle.net/hearthstone/en/blog/19995505/a-new-way-to-play-2-2-2016
Huge announcement by Blizzard regarding Hearthstone with the move to introduce game formats to the game; Standard and Wild. It is quite similar to the formats in Magic: The Gathering. For Standard in Hearthstone, the Basic and Classic set will not be rotating so Classic packs are probably one of the best pack to buy at the moment if you are still missing key cards from there. I've stopped spending coins as I have most of the cards required to build the decks I want and even with the Standard format, I should be spending my coins on the latest spring expansion as it is always nice to experiment with new cards.
More deck slots were also announced but when I checked the Hearthstone reddit, there wasn't much posts about it in the first few pages which is strange for something much asked for! It seems that mostly the format change had quite an impact on the Hearthstone community that everyone was talking about it instead.
Standard's introduction in Spring will "rotate" out Curse of Naxxramas and Goblins vs Gnomes and there are so many staples from those sets that cannot be used; Zombie Chow, Haunted Creeper, Webspinner, Mad Scientist, Piloted Shredder, Antique Healbot, Loatheb, Sludge Belcher, lightbomb, shielded minibot, muster for battle, death's bite and the infamous Dr. Boom! They are definitely still usable in Wild mode and solo play and should be helpful in Adventures and the Heroic quests.
I look forward to Standard format as it should shake up deck building and keep things fresh with each rotation!
Edit: I realised I forgot about this line from the official article, "While normally we’re quite conservative about making balance changes to Hearthstone cards (and we’ll continue to be in the future), we’re planning to take the new Hearthstone year as a golden opportunity to re-evaluate a number of cards in the Basic and Classic card sets, including class cards, and make some long-considered adjustments." It looks like there is going to be a number of card changes!
More Readings:
https://tempostorm.com/articles/hearthstone-gone-wild
https://tempostorm.com/articles/the-inevitability-of-standard-mode
