If you do not have a way to counter it, keep your opponents board clear or their graveyard empty, you will never get rid of Recurring Nightmare
This card might as well say, "as long as you control a creature, you cannot lose the game." 17
Farseek This is the only entry on my list that cannot be used in monogreen decks, but omitting it simply isnt an option when discussing the best green ramp spells
Granted, those decks are almost all focused on milling out the opponent but the original Hedron Crab is also able to target yourself, which makes it one of the most explosive and mana-efficient self-mill engines ever printed
Abzan Control Suspension Field +4 Boon Satyr -4 Silkwrap Suspension Field kills all of Abzan's key creatures except Nissa and Den Protector
Trance At the beginning of combat on your turn, mill two cards