Ultraman: I Built a Transformation Device by Hand and Became Ultraman!

An unknown dark force has engulfed the entire Ultra universe. To put an end to the crisis, Lin Yi, director of the Capture Division at the Transmigration Bureau, takes on this SSS-rank mission without hesitation for the sake of a rare vacation. But the moment he sets out, he encounters an unprecedented crisis! Lin Yi knows the coordinates of his destination, but has no way to travel directly to the world of Ultraman Tiga! Luckily, at the crucial moment, Kamen Rider Decade comes to his aid and sends Lin Yi to the world of Ultraman Tiga. [The protagonist transforms in Chapter 9. He makes his own transformation device, so it takes a little longer.]