Seaman's face is actually that of the game's producer and creator, Yoot Saito. Saito also acts as Seaman's Japanese voice actor. During development, Sega had requested that a celebrity be used if possible to voice Seaman, but Saito was hesitant. He later said in a 2020 interview that the fact that he played the role himself was "the key to success", because it gave him the advantage of being able to rerecord lines as many times as he wanted, so it was no longer a question of money.