For the moment I would say Slimefoot, the Stowaway. I went all in on it as a combo deck with ways to make tons of Saproling tokens and sacrifice them. I also added in Grafted Exoskeleton and some ways to buff the tokens and Exsanguinate as a way to use infinite mana if needed.
amazingly epic sig courtesy of DarkNightCavalier at Heroes of the Planes.