Cast Notorious Throng for its prowl cost by paying 5, causing you to take an extra turn after this one.
Move to your next turn.
Cast Chthonian Nightmare by paying 1.
When Chthonian Nightmare enters the battlefield, it triggers, causing you to get EEE.
Activate Chthonian Nightmare by paying EEEEE, sacrificing a creature with mana value 2 or less, and returning Chthonian Nightmare from the battlefield to your hand, returning Pinnacle Monk from your graveyard to the battlefield.
When Pinnacle Monk enters the battlefield, it triggers, returning Notorious Throng from your graveyard to your hand.
Cast Chthonian Nightmare by paying 1.
When Chthonian Nightmare enters the battlefield, it triggers, causing you to get EEE.
Activate Chthonian Nightmare by paying at most E, sacrificing Pinnacle Monk, and returning Chthonian Nightmare from the battlefield to your hand, returning a creature with mana value 1 or less from your graveyard to the battlefield.
Repeat.
This clever loop turns the extra turn granted by Notorious Throng into an infinite loop by recycling resources through the graveyard. Chthonian Nightmare acts as the engine, using its energy generation and sacrifice ability to repeatedly pull Pinnacle Monk—whose front side functions as an adventure or dual card—back onto the battlefield from the graveyard. Each time Pinnacle Monk enters, its triggered ability retrieves Notorious Throng right back to your hand so you can cast it again on your subsequent turns, completely locking down the game with endless actions.