Heroes of the Storm Kel'Thuzad Tease

A new "Obey the Call" trailer for Heroes of the Storm is now online, promoting the upcoming addition of Kel'Thuzad to the Nexus. This takes a different form from their recent hero cinematics, as it's in the style of an animated cartoon. There is also a new Kel'Thuzad page on Battle.net outlining his abilities as an assassin in the MOBA. For those unfamiliar with the Archlich of Naxxramas from World of Warcraft, they also offer an overview:
Kel'Thuzad has faithfully served the Lich King both in life and after death. Reanimated as the Archlich of the Scourge and given domain of the Dread Necropolis, Naxxramas, Kel’Thuzad remains Arthas’s most trusted advisor and master of the cold dark.