How do laser tag beams show up in black lights and how can i modify my toy guns to do the same?

Answer 1

The ability to see laser beams has nothing to do with black lights. Lasers need a reflective property in order to be seen by the human eye. Often times, the reflective property is a simulated fog in laser tag arenas.

Something as simple as air freshener can be used as a reflective property in order to see a laser beam.