Riku of Two Reflections | Narset's Reversal | Notorious Throng

Cards

Riku of Two Reflections on the battlefield.
Narset's Reversal and
Notorious Throng in hand.
You control at least one Rogue that does not have summoning sickness and cannot be blocked by an opponent.
({5} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) ({R} magic symbol) each turn available.

Deal combat damage to an opponent using a Rogue.
Cast
Notorious Throng for its prowl cost by paying ({5} magic symbol) ({U} 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
Notorious Throng.
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
Notorious Throng, and returning the original
Narset's Reversal to your hand.
Resolve the copy of
Narset's Reversal created in step 5, copying
Notorious Throng and returning the original
Notorious Throng to your hand.
Resolve
Notorious Throng, causing you to take an extra turn after this one and create a number of 1/1 Faerie Rogue creature tokens.
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.