The most obvious change will be the card shift. The sets from 2016 -- Whispers of the Old Gods, One Night in Karazhan and Mean Streets of Gadgetzan -- will all pass out of Standard format to make way for the new expansion. This is has traditionally been the best time of year for new players to jump in the game, since it has the least amount of cards in play, but the switchover also refreshes the meta of competitive decks and strategies. While this year's three sets are still shrouded in mystery, they will all have free single-player adventure content -- hopefully they'll be as inventive and enjoyable as the Arena-like Dungeon Run that came with the most recent expansion Kobolds & Catacombs.
But 2016's cards won't be the only ones joining the Wild format. Three old favorites will be added to the Hall of Fame, the honorific category Hearthstone's team created last year to retire cards from the previously-immune Classic set that launched with the game. 2017's entries included fan-favorites like Ragnaros the Firelord, Sylvanas Windrunner and Azure Drake, which Blizzard put out to pasture for being auto-includes in most decks that were also becoming too difficult to design around. This year's Hall of Fame slate is much the same: Ice Block and Coldlight Oracle are both being retired for defining decks for years.
Curiously, Molten Giant is also getting Hall of Fame'd with his 5-mana nerf reverted to its original cost; The Hearthstone team might be doing this as a gift for veteran fans to resurrect old decks in Wild. If you own any of these cards, you'll get a full dust reward as if you'd disenchanted them -- which can result in some free dust if you manage to craft them beforehand and dismantle them after, as this guide explains.
The new year and next set will probably bring back casual and absent players curious about the next smattering of cards, but those who have been away for awhile will have to play catch-up on expansions and strategies they missed out on. To get over that 'homework hump,' Hearthstone is handing out a new Druid hero portrait for free (much like they did for 2017's first new set). Players will earn Lunara, the gleeful dryad that Heroes of the Storm fans will recognize, after winning 10 games in the Standard format.
The most exciting change won't be new cards or content, but the ability for any player to create their own tournament within the game client. Just set up the rules and hit 'launch' -- Hearthstone will matchmake and check decks to make sure they fit your bonkers theme (Lorewalker Cho + Faceless Manipulator + Mirage Caller, let's go). The beta will come later this year at an undetermined time, so in all likelihood, don't expect it alongside the first expansion.
Finally, the new year will bring more international stops for the 2018 Hearthstone Championship Tour, which the Hearthstone team announced beforehand. Check up their blog post to see the new schedule. That's all we know about the Year of the Raven thus far, but fans should keep an eye out for news of 2018's first expansion that's likely to drop in the coming weeks. And if they have any questions, Hearthstone 's game director Ben Brode and senior producer Yong Woo will host a live Q&A on the game's Twitch channel at 11am PT on March 2nd.