with questions having a common theme the knowledge based playing step of the bonus game includes the step of asking the player questions the value of which is measured against survey responses the knowledge based playing by the step of answering selecting or guessing includes the step of asking questions of varying difficulty the step of awarding includes the step of first achieving a predetermined yet random event in the underlying game of chance to begin play of the bonus game the expected value of the bonus game is fixed regardless of player proficiency in the bonus game the awarding step of the bonus game happens with the wagering of x units to be eligible for the bonus game with a frequency f and with the expected return r units for an underlying game without the bonus and with bonus participation on average garnering the expected bonus value of b units and wherein the step of calculating the house advantage as equal to u2212 r f b u2212 x x the step of adding to the at least one escrow account includes the steps of dividing into a current escrow account and a reserve escrow account the step of dividing includes putting a bigger share into.