I have seen turn one mana dork into turn two Explorer, discard a Vengevine and get a land to play another one drop and return the Vengevine for about 10 power in play turn two, nearly half of it attacking right away
Four mana to destroy all creatures is the benchmark, and these spells will do it
Its also quite old and obscure, with just a single Urzas Saga printing to its name
This makes it almost impossible for players to attack you without a concerted effort, setting you up to be in a leading position from early on in the game
You can choose no gap for cards that are directly adjacent, 0.2 mm as the default for general use, or 3.0 mm to allow for a bleed area
I think it's within the range of adoption for a normal Green deck, as there are many times you'll want a trade-fodder unit for 2 mana