The first Mahou Shoujo Taisen illustration contest by 2.5 Dimension TV on Pixiv.
It ran from 2012-6-28 to 2012-8-8 and there were 3248 entries.
Contest terms
Contestents were asked to draw original magical girls representing one of Japan's 47 prefectures. Along with the magical girl, they also needed to include a magical pet and magic wand.
Contest results
Grand Prize (The terms said at least 1, but they awarded 3) - Prize: 50,000 yen and a 3D model of your character
