While this may be an uncommon draw requiring a very specific combination of cards and mana, the deck is very capable of producing relatively common Turn 4 kills
At the beginning of your upkeep, this creature deals X damage to target opponent previously dealt damage by it, where X is the number of infection counters on it
You are trading both the spell and the sacrificed land for any land from your deck
(Worth noting is that when Infested Thrinax enters the battlefield for the second, third, and so on time each turn, whether through this loop or some other means, each instance of Saproling creation will stack, so you start generating Saps faster with each loop.) Infinite mana, tokens, enters/leaves the battlefield (or leaves the graveyard, hello Insidious Roots!) effects for you to use how youd like
For the back face, as we had two other green cards with Dinosaurs on the back, we decided to make it an Ooze