Chthonian Nightmare | Ardent Elementalist | Walk the Aeons

Cards

Ardent Elementalist in your graveyard.
Chthonian Nightmare and
Walk the Aeons in hand.
You control a nontoken creature with mana value 2 or less.
You have at least ({E} magic symbol) .
({4} magic symbol) ({U} magic symbol) ({U} magic symbol) the first turn, with ({6} magic symbol) ({U} magic symbol) ({U} magic symbol) ({B} magic symbol) ({B} magic symbol) each extra turn available.

Cast
Walk the Aeons by paying ({4} magic symbol) ({U} magic symbol) ({U} magic symbol) , causing you to take an extra turn after this one.
Move to your next turn.
Cast
Chthonian Nightmare by paying ({1} magic symbol) ({B} magic symbol) .
When
Chthonian Nightmare enters the battlefield, it triggers, causing you to get ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) .
Activate
Chthonian Nightmare by paying ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) , sacrificing a creature with mana value 2 or less, and returning
Chthonian Nightmare from the battlefield to your hand, returning
Ardent Elementalist from your graveyard to the battlefield.
When
Ardent Elementalist enters the battlefield, it triggers, returning
Walk the Aeons from your graveyard to your hand.
Cast
Chthonian Nightmare by paying ({1} magic symbol) ({B} magic symbol) .
When
Chthonian Nightmare enters the battlefield, it triggers, causing you to get ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) .
Activate
Chthonian Nightmare by paying at most ({E} magic symbol) ({E} magic symbol) , sacrificing
Ardent Elementalist, and returning
Chthonian Nightmare from the battlefield to your hand, returning a creature with mana value 2 or less from your graveyard to the battlefield.
Repeat.