mtg no cards in library General - Custom Cards: The Lab | Page 49 | Riptide Lab Stillness in Motion - Tarkir:

Prosperous Innkeeper is very valuable for our Halfling Food Tribal because of its lifegain ability (On another creature EtB under our control, we gain 1 life), but on EtB it creates a Treasure token so it helps a bit with ramp too

The controller of a copy can't choose to pay any additional costs for the copy

Midrange wins by turning the corner fastif you stabilize and then sit around, you give your aggro opponent a chance to draw burn spells or reload

Combine this with Angelic Skirmisher (which almost made the Honorable Mentions list) for extra fun

Well, the deck only has 18 sources for each (counting Gemstone Cavern), which pulls the reliability down to 87%