Chthonian Nightmare | Peregrine Drake (and one other card)

Creature with MV<=1

Cards

You have at least ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) .
You control up to five lands that can tap to produce at least ({2} magic symbol) ({B} magic symbol) ({B} magic symbol) .

Activate up to five lands by tapping them, adding at least ({2} magic symbol) ({B} magic symbol) ({B} magic symbol) .
Activate
Chthonian Nightmare by paying at most ({E} magic symbol) , sacrificing
Peregrine Drake 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.
Cast
Chthonian Nightmare by paying ({1} magic symbol) ({B} magic symbol) .
When
Chthonian Nightmare enters the battlefield, it triggers, giving you ({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) ({E} magic symbol) , sacrificing a nontoken creature with mana value 1 or less and returning
Chthonian Nightmare from the battlefield to your hand, returning
Peregrine Drake from your graveyard to the battlefield.
When
Peregrine Drake enters the battlefield, it triggers, untapping up to five lands.
Cast
Chthonian Nightmare by paying ({1} magic symbol) ({B} magic symbol) .
When
Chthonian Nightmare enters the battlefield, it triggers, giving you ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) .
Repeat.
If the five lands can tap to produce at least ({3} magic symbol) ({B} magic symbol) ({B} magic symbol) , this combo nets infinite mana.

This combo has been estimated to be Exhibition (Bracket 1+).