Riku of Two Reflections | Narset's Reversal | Alchemist's Gambit

Cards

Riku of Two Reflections on the battlefield.
Narset's Reversal and
Alchemist's Gambit in hand.
({4} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) ({R} magic symbol) ({R} magic symbol) each turn available.

Cast
Alchemist's Gambit for its cleave cost by paying ({4} magic symbol) ({U} magic symbol) ({U} magic symbol) ({R} magic symbol) .
Riku's first ability triggers - choose not to pay.
Holding priority, cast
Narset's Reversal by paying ({U} magic symbol) ({U} magic symbol) , targeting
Alchemist's Gambit.
Riku's first ability triggers, causing you to pay ({U} magic symbol) ({R} magic symbol) to copy
Narset's Reversal, with the copy targeting the original
Narset's Reversal.
Resolve the copy of
Narset's Reversal, copying the original
Narset's Reversal targeting
Alchemist's Gambit, and returning the original
Narset's Reversal to your hand.
Resolve the copy of
Narset's Reversal created in step 5, copying
Alchemist's Gambit and returning the original
Alchemist's Gambit to your hand.
Resolve
Alchemist's Gambit, causing you to take an extra turn after this one.
Repeat each turn.

You may pay an additional ({U} magic symbol) ({R} magic symbol) to copy the extra turn spell, and only need to do this loop during your second extra turn.