You control creatures that can tap to produce at least ({3} magic symbol) .
Steps
Activate Tezzeret's second loyalty ability by removing a loyalty counter on it, causing Isochron Scepter to become an artifact creature until end of turn.
Activate creatures you control by tapping those, adding at least ({3} magic symbol) .
Activate Isochron Scepter by paying ({2} magic symbol) and tapping it, casting a copy of Vitalize without paying its mana cost, untapping all creatures.