The player may decide whether or not to select Mystery Options. If he chooses not to take them, then he is deemed to know everything a character should know about himself--there are not surprises in his character, his history, or his family history. However, if he chooses Mystery Options, there are things which he does not know about his character, which he may discover--for better or for worse--during the campaign.
The player choosing Mystery Options may select any die and roll it. The referee may allow a character eager to have many surprises to select two (different) dice and roll them. Both the die selected and the number rolled are significant, and both should be recorded.
The number rolled determines the number of discrete facts the character does not know about himself. If the roll is above 16 (e.g., on a d20), the character has amnesia, and does not know his name, his class, or any details about himself when the game begins. The most important information--especially class--will be revealed immediately ("is this your spell book?"), but there will be very little the character knows about himself. On one occasion, a hengeyokai sparrow kensai rolled a 27 (on a d30), and began the game as a sparrow purchased by one of the player characters to detect cave gas. He discovered he was not a sparrow when another party member, a hengeyokai, spoke with him, and recognized that he could speak hengeyokai.
The number of sides on the die determines the significance of the things the character doesn't know. The lower the number of sides on the die, the more significant these things are. If a d4 is rolled, things not known can include that the character is not the natural child of those he believes are his parents, that he is not the race he believes he is (an elf might be a half-elf or an irda), that he was chosen at (or before) birth for some special destiny. On the other end of the spectrum, if a d20 is selected, the unknown information can be on the order of one of his ancestors was allied with an immortal or ancient still active in the world today, he is a distant cousin (or a look-alike) of an important ruler, a piece of his equipment is actually an important or legendary magic item or significant token (a signet ring, for example), or that someone believes he has committed some wrong for which vengeance must be taken.
Although the referee may find it useful to have a list of possible mystery options from which to draw, it is best to develop the options for each character individually, based on the roll, the nature of the character, and the direction the game takes.
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