Any idea how to spot and catch him?


I heard a tone but not always find him. When I found him and click, most of the time it doesn't work. Then disappeared in a second.

He vanishes a few seconds after the room he's in is on your screen. When you hear the tone, it will be loud or soft in volume. The louder it is, the closer he is to wherever you were looking at the time. Search quickly! Once you hit the room he's in, he will start to disappear in a few seconds.

Most of the time he's only worth a few caps. Sometimes, though, he's worth a bundle.

If you need to find him for objectives or something try this:

Zoom out to 2D - easier to locate him from there

Wear earphones - the sound will actually help to indicate the position then