Magical Girl Raising Project, Vol. 2 (light novel‪)‬

(Volume 1)
The hit social network game "The Magical Girl Raising Project" selects one out of every tens of thousands of players to become a real life magical girl. The lucky chosen girls gain magic powers as well as incredibly good fortune, and spend their days blissfully.
But one day, an absolute announcement declares that the number of magical girls has risen too high and must be cut down to half. Sixteen young maidens are thrust into a merciless, deadly contest to survive...but how many will come out the other side?