1Cast Mystic Reflection either from your hand by paying or from exile for its foretell cost by paying , choosing Exalted Sunborn.
2Cast Storm Herd by paying , creating a number of 1/1 Pegasus creature tokens equal to twice your life total that enter as copies of Exalted Sunborn due to Mystic Reflection.
3Whenever you create one or more tokens, you will instead create 2^X times that many tokens, where X is the number of Exalted Sunborns you control.