If it is the "Adventures of Robbo" game listed here then I don't know which one is the magnet or magnetic field.
But I guess you mean the red beam like laser field or whatever it is. If that's the case then you should take a look at Alan's BD2k3, where it has been implemented in several levels.
Francesco wrote:I don't know that game, so I can't guess what's the desired behaviour. Explain it in detail and you'll get prompt help for sure
http://www.youtube.com/watch?v=CZ3rAiECMwc
Maybe this movie help. Magnet is in the upper left corner of level.
If player (robot) is in this same line then the magnet take player to it, kill him and you must play level again.