Medivh wants you to come to his party. Hopefully he hasn't invited any Warrior mains.

The rumours were true. Hearthstone’s next single-player Adventure will take place in the magical tower of Karazhan, where the powerful mage Medivh has gone AWOL from his own party. The expansion is called One Night in Karazhan , and it starts on August 11. Alongside Medivh's butler Moroes, who will also be a legendary card, it will be up to you to find the errant wizard, unlocking 45 new cards in the process, which will be dropped from four wings that will unlock weekly.

The new adventure was just announced on Twitch by senior designer Ben Brode at the ChinaJoy expo in Shanghai. He showed the new board, which is themed around an enchanted chess set, and seven Karazhan cards, five of which are class specific. Interestingly, Blizzard has chosen not to spoil the new Priest card yet. I wonder if the class is going to get something special, given it’s widely considered to be dumpster tier currently. Check out the cards spoiled so far in the gallery below, with some initial thoughts on their potential power. Just click the arrows to cycle through the cards.

Image 1 of 7 Enchanted Raven As someone who’s played a lot of Druid, this is interesting to me. Even before the nerf to the Force of Nature-Savage Roar combo, Blizzard was pushing the class down the road of Beast synergy. This card enables that, and also helps shore up Druid’s traditionally weak early game. (Notably, it’s the first 1-Mana 2/2 printed.) Would you play Enchanted Raven over Living Roots? Maybe. It’s less flexible, and doesn’t buff your Yogg, but will trade cleanly with most other one-drops. Should see play, if only because this into Mark of Y'Shaarj is an insane opener. (Enchanted Raven is also a stealth nerf to Ram Wrangler!) Image 2 of 7 Kindly Grandmother Just as Druid is being pushed towards Beast stuff, so Hunter is steadily becoming the Deathrattle class. A 2-Mana 1/1 won’t necessarily fix Hunter’s early game issues, which at one point saw MrYagut running Doomsayer, but on the upside it’s a Beast which leaves another Beast behind. That will help with activating Houndmaster, Kill Command and Ram Wrangler. Perhaps still too slow against Shamans, but Hunter likes sticky cards and this will also see play. If nothing else, the art is awesome. Image 3 of 7 Firelands Portal I’m less sold on this Mage spell. Does the class really need more burn spells? That said, being able to remove something from the board, at the same time as developing a minion on your side, is a powerful tempo effect. Effectively, you’re paying 2-Mana for 5 damage, which is a pretty good deal, depending on how the RNG on your 5-drop rolls. Sensational if you get a 7/8 Earth Elemental. Less so if it's a 3/3 Faceless Manipulator. Interestingly, Frodan revealed on stream that there will be five portal cards in total. Image 4 of 7 Ivory Knight Paladin gets a 4/4 for 6, which is obviously super weak, but as we’ve seen from Raven Idol, the attached Discover spell effect is potentially powerful. Tacking on bonus healing means that the ultra-grindy Healadin builds will be even more viable. Again, I’m confident this will be used, even if it’s a bit ResidentSleeper. Image 5 of 7 Ethereal Peddler The 5/6 statline for 5-Mana is reasonable, but does Rogue need more midrange minions in a world in which they already have Tomb Pillager? The Battlecry effect is interesting for its synergy with Burgle and Undercity Huckster, but it relies on you having the resulting cards in hand when you play the Peddler. A bit too situational for my liking, and given that Shadow-Pan Rider isn’t seeing any play outside Arena, my gut feeling is that this won’t either. Image 6 of 7 The Curator Okay, this neutral Mech legendary with Taunt looks dumb at a glance. But I like it. Maybe a lot. Obviously it’s a “build around” card. It’s too early to say what the best class for The Curator will be, and you definitely aren’t looking for a multi-tribal synergy deck—but don’t forget how powerful an effect drawing specific cards on cue can be. Imagine using this in, say, Midrange Paladin, in order to refill your hand with Ysera, Mukla Tyrant of the Vale and, uh, Murloc Knight. Okay, that’s probably madness. But trust me, a lot of streamers are going to try to make this work. Image 7 of 7 Barnes Another neutral legendary, and at 4-Mana it’s possible to compare Barnes to Elise Starseeker and Fandral Staghelm. The fact he loses one point of Health suggests his effect is a powerful one, which I guess it will be if he pulls a 1/1 version of Sylvanas, Cairne, Ysera, Tirion or some other gross legendary from your deck. But if he grabs your 2-drop, probably not so much. Still, interesting, and so far all the cards look like they’ll at least be experimented with. I was initially not sold on Barnes, partly because Herald Volazj has a similar effect and has seen precisely no play. But summoning is very different to copying, in that you don’t need to have any board presence for it to be good. On that basis, Barnes could be pretty strong, in an infuriating RNG sort of way. Art looks a bit Saturday morning cartoon for my taste though.

Ben Brode talks One Night at Karazhan at ChinaJoy "This party is going to be legendary. You arrive one hour before the party starts and Medivh is missing. The spells that's he cast are beginning to unravel. You need to find Medivh and save the party."

One Night in Karazhan will work much the same as previous Hearthstone adventures like Curse of Naxxramas and The League Of Explorers. Each wing will have bosses to overcome in both normal and heroic difficulty flavours, plus class challenges that reward their respective class-specific cards. The whole package can be pre-ordered from the in-game shop for $19.99, otherwise individual wings will cost 700 gold or $6.99 each.

Here’s the official spiel about the game: “As Azeroth’s most powerful mage, Medivh’s magical prowess is surpassed only by his love for extravagant shindigs, and he has spared no expense to entertain his cherished guests—lavish feasts, impeccable Opera performances, and more await you inside.” Having not played the original World of Warcraft Karazhan raid which the set is based on, I’m essentially imagining it’s a '70s funk version of Disney’s Fantasia, but with greater casualties. Here’s a video showing one of the encounters.

Because Blizzard likes to give potential addicts a taste of the product first, you’ll also be able to sample one prologue mission for free, which will score you two of the cards. As usual, there’s also a promotional card back on offer for players who purchase up to the end of the first week, and another card back if you can beat all the bosses on Heroic difficulty. Which in my experience means a visit to Hearthpwn to source a cheeseball deck that hard counters the boss’s hero power. Or you could try and sleuth a deck solution yourself. But honestly where’s the fun in that?

Hearthstone’s last adventure, The League of Explorers, set a high bar to follow due to its high impact legendary cards. Hopefully One Night in Karazhan can keep the pace up, because with the ladder overrun by Warrior decks of every flavour, the meta could certainly use a shakeup. The new board and cinematic trailer are below.