Flowey, World's Bane

Flying
As long as an opponent controls less than 5 Human Spirits, Flowey, World's Bane has Indestructible, Shroud, and "Whenever a source would deal damage to you or give you life, that amount is reduced to 1."
At the beginning of your upkeep, if you didn't control a Human Spirit creature at the start of your last turn, search your library for a Human Spirit creature and put it onto the battlefield. Then shuffle your library.