Activate Metalworker by tapping it, causing you to reveal at least two artifact cards from your hand and add at least ({C} magic symbol) ({C} magic symbol) ({C} magic symbol) ({C} magic symbol) .
Activate Gemstone Array's first ability by paying ({2} magic symbol) , putting a charge counter on it.
Activate Gemstone Array's second ability by removing a charge counter from it, adding ({U} magic symbol) .
Activate Pemmin's Aura's first ability by paying ({U} magic symbol) , untapping Metalworker.