Fire Lord Azula | Narset's Reversal | Valley Floodcaller (and one other card)

Cards

Narset's Reversal and
Walk the Aeons in hand.
Fire Lord Azula and
Valley Floodcaller on the battlefield (
Fire Lord Azula without summoning sickness).

({2} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) each other turn available.

Declare
Fire Lord Azula as an attacker, triggering its firebending ability, adding ({R} magic symbol) ({R} magic symbol) .
Holding priority, cast
Walk the Aeons by paying its mana cost.
Fire Lord Azula's second ability triggers, copying
Walk the Aeons.
Holding priority, cast
Narset's Reversal by paying ({U} magic symbol) ({U} magic symbol) , targeting the original
Walk the Aeons spell.
Fire Lord Azula's second ability triggers, copying
Narset's Reversal, targeting the original
Narset's Reversal.
Resolve the copy of
Narset's Reversal, causing you to copy
Narset's Reversal targeting the original
Walk the Aeons spell, and then return the original
Narset's Reversal to your hand.
Resolve the copy of
Narset's Reversal, copying
Walk the Aeons and returning the original
Walk the Aeons to your hand.
Resolve both copies of
Walk the Aeons from steps 3 and 7, causing you to take two extra turns after this one.
Repeat during your second extra turn.

This combo has been estimated to be Ruthless (Bracket 4+).