Nonland permanents you control can tap to produce at least ({4} magic symbol) ({UR} magic symbol) ({UR} magic symbol) ({U} magic symbol) .
Steps
Activate all mana producing nonland permanents you control by tapping them, adding at least ({4} magic symbol) ({UR} magic symbol) ({UR} magic symbol) ({U} magic symbol) .
Activate Soulfire Grand Master by paying ({2} magic symbol) ({UR} magic symbol) ({UR} magic symbol) , causing you to put the next instant or sorcery spell you cast this turn into your hand as it resolves.
Cast Dramatic Reversal by paying ({1} magic symbol) ({U} magic symbol) , untapping all nonland permanents you control and putting Dramatic Reversal into your hand as it resolves due to Soulfire Grand Master.
Repeat.
Results
Infinite magecraft triggers.
Infinite mana nonland permanents you control can produce.