Compared with other characters, Hatsune Miku and friends must be the most popular guest stars, popping up in a variety of games over the years in Japan. The latest collaboration is with Mirror War, a newly launched online arcade shooter under Gamepot. There is even a trailer to boot!
As you can see, there will be special costumes and in-game combat effects. According to my observations, Mirror War is doing ok in South Korea, lukewarm in Indonesia, but supposedly well anticipated in Japan. There is supposed to be an English SEA server in the works as well.