You control a nontoken noncreature artifact with mana value one or less.
Steps
Activate Chromatic Orrery's first ability by tapping it, adding at least ({5} magic symbol) .
Cast Ancestral Statue by paying ({4} magic symbol) .
When Ancestral Statue enters the battlefield, it triggers twice.
Holding priority, activate Clock of Omens by tapping the nontoken noncreature artifact with mana value one or less and by tapping Ancestral Statue, untapping Chromatic Orrery.
Resolve both Ancestral Statue triggers, returning it and the nontoken noncreature artifact to your hand.
Cast the noncreature artifact by paying its mana cost.
Repeat.
If the noncreature artifact has a mana value of zero, this combo nets infinite mana, which would allow you to instead use Chromatic Orrery's second ability to draw infinite cards.