At the end of each turn, summon all friendly minions that died this turn.
Kel'Thuzad could not resist the call of the Lich King. Even when it's just a robo-call extolling the Lich King's virtues.
How to get:Unlocked in Frostwyrm Lair, in the Naxxramas adventure.
How to get Gold:Crafting unlocked in Frostwyrm Lair, in the Naxxramas adventure.