Lightning Carnival
From PSU Cyril Wiki
The Dengeki Mission Carnival is a special event exclusive to the Japanese PC/PS2 servers which is sponsored by Dengeki PlayStation, a popular Japanese gaming magazine. Though this event has not yet been confirmed for release outside of Japan, as with all previous events, it is expected to make its way to the English PC/PS2 and international Xbox 360 servers at some point in the future. Of course, Dengeki will likely not be associated with it, so a new name to the event is expected.