March of the Lich King is Hearthstone's 22nd expansion, featuring new 145 collectible cards released on December 6, 2022. The expansion depicts the return of The Lich King, as he leads his Undead army to an all-out assault on the elven city of Silvermoon. The Blood Elves won’t go down easily; they are as thirsty for combat as they are for the magic of the Sunwell that they draw power from. March of the Lich King introduces Hearthstone's 11th total and second-ever new class, the Death Knight. The expansion also introduces a brand new permanent minion type - Undead. Undead minions trigger bonus effects if a friendly Undead minion died after the player's last turn. In addition to that, March of the Lich King introduces dual minion types, meaning some minions can have two different minion types. Both Undead and dual minion types are retroactively added to all cards from the past. Manathirst is March of the Lich King's new keyword. Cards with Manathirst get more powerful once the player reaches a specified amount of mana. Mana isn't required to be spent to power up the cards, but that much mana must be in the player's control. In addition to Manathirst, Reborn from Saviors of Uldum returns as a permanent keyword going forward, and can be seen on Undead minions in March of the Lich King.