Sin & Punishment: Successor of the Earth (Tsumi to Batsu: Hoshi no Keishōsha) is a sensational rail shooter for the N64 designed by Treasure. Standing out are the ludicrous plot, obscure dialogue ("ruffians have never appeared in America"), cast of androgynous characters, doom laden ambient techno soundtrack, eclectic control system and awesome enemy and level design. I should also note that there are more bosses in this game than in almost any other, in fact there are probably more bosses than normal soldiers! However I believe Treasure are addicted to labelling any enemy that requires more than one shot to kill 'a boss' so maybe take the last sentence with a pinch of salt.
Walthrough at GameFAQs
Great Article at Hardcore Gaming 101
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