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[edit] Speculation

Master-class is a rating of the power level of a Caster.^Erf-b1-p127

The term suggests that a certain level has been attained by the caster.

Individual schools of magic may have their own titles (such as Grand Abbie, the rank held by Janis) in addition to the generic designation. The relationship between such titles and the general proficiency level implied by "Master-class caster" is still unclear.

Mastermind is a term for Master-class Thinkamancer.

Any caster can gain Master-class by a caster gaining a powerful new insight into their discipline or major class. Book 2 Text Update 50

[edit] Known Masters

• Wanda, Turn 8 AW, as a Croakamancer.^{TBFGK 127:10} Note that as a Thinkamancer, however, Turn 6 AW, Wanda was merely Novice-class.^{TBFGK 84:7}
• Jack Snipe, a master-class Foolamancer (at least when he was working for FAQ).^{TBFGK 107:6}