On March 29, 1997, there was an incident involving the episode The Mysterious Father! (1997) in which four children were taken to hospitals after reportedly watching a scene in the episode with rapidly flashing red and white colors. Later broadcasts of this episode were edited so that the flashes were not as fast, unlike the infamous Pokémon episode Dennô Senshi Porygon (1997), which was banned.
There are three manga series, one by Shinji Nishikawa in 1996, another by Yutaro Kawamoto in 1997 and a third by Shinji Nishikawa released in 1998.