Saheeli, Sublime Artificer | Mirror of Fate | Karn's Temporal Sundering

Cards

({5} magic symbol) ({U} magic symbol) ({U} magic symbol) ({UR} magic symbol) ({UR} magic symbol) each odd-numbered turn, with ({4} magic symbol) ({U} magic symbol) ({U} magic symbol) available each even-numbered turn available.

Cast
Karn's Temporal Sundering by paying ({4} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Saheeli triggers, creating a 1/1 Servo artifact creature token.
Resolve
Karn's Temporal Sundering, causing you to take an extra turn after this one, return
Saheeli from the battlefield to your hand if
Saheeli has fewer than three loyalty counters, and exile
Karn's Temporal Sundering.
Cast
Saheeli by paying ({1} magic symbol) ({UR} magic symbol) ({UR} magic symbol) if it's in your hand.
Activate
Saheeli by removing two loyalty counters from it, causing the Servo to become a copy of
Mirror of Fate until end of turn.
Activate the Servo by tapping and sacrificing it, choosing
Karn's Temporal Sundering and up to six other cards face up in exile, then exiling your library and putting the chosen cards on top of your library, with
Karn's Temporal Sundering being the top most card.
Move to your next turn, drawing
Karn's Temporal Sundering during your draw step.
Repeat.