Deleted

It is Magicka DLC: The Stars are Left
But I don't have original game ,too! Thanks!
https://steamdb.info/sub/12336/

I already own it. It's a dlc for magicka called the stars are left. It's probably used by someone already since steam doesn't tell if a game is activated by a different account if one already owns that game.

Just an FYI: Someone did use the key as it's showing it's a duplicate product code for me.