Anti-Magic Shell

The following spell name is directly taken from Blizzard, but I owe nothing related to World of Warcraft nor Blizzard. I merely wish to bring the spell to the masses. All rights go to Blizzard Entertainment.

Creator note: This spell might feel extremely powerful, and probably is, so make sure to consult your DM before use. I made it with the Death Knights from the World of Warcraft universe in mind, therefor making it powerful.    

You form a green-runed necrotic barrier around you that nullifies magic! Until the end of your next turn, you are immune to magical damage and effects.