Emiel the Blessed | Preston, the Vanisher | Delney, Streetwise Lookout (and one other card)

Cards

Activate
Emiel the Blessed by paying ({3} magic symbol) , blinking
Prosperous Innkeeper.
When
Prosperous Innkeeper enters the battlefield, it triggers twice, and
Preston trigger twice if it has power 2 or less, or once otherwise.
Resolve both
Prosperous Innkeeper triggers, creating two Treasure artifact tokens.
Resolve the first
Preston trigger, creating a token copy of
Prosperous Innkeeper that is a 0/1 Illusion.
When the
Prosperous Innkeeper token enters the battlefield, it triggers twice, creating two Treasure tokens.
Repeat from step 4 for the remaining
Preston trigger, if applicable.
Activate three Treasures by tapping and sacrificing them, adding ({3} magic symbol) .
Repeat.

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