While Eidolon has a creature version of Pyrostatic Pillar, a powerful burn card in its own right, Cemetery Gatekeeper is like a more flexible creature version of Ankh of Mishra
What makes Greater Good so good is that its ability is instant speed and it sacrifices
Sylvan Safekeeper A card like Sylvan Safekeeper will find a way
(To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.) Flavor Text The dead know lessons the living haven't learned
Then each of your opponents may do the same, and each time an opponent does, you get to find and play another land
This flies in the face of the argument that occasionally comes up from the MTG Finance community (many of whom have a vested interest in the Reserved List) saying we should simply stop talking about the Reserved List and accept its currently detrimental impact on the game