However, if an effect instructs you to search your library for a card with a basic land type, you must search for a land that is a Plains, Island, Swamp, Mountain, or Forest, regardless of whether or not the land is basic
As mentioned, Codsworth is decently popular in Commander, and theyre not exactly the most common MTG card
Daretti, Rocketeer Engineer Goblin Up Your Graveyard While the Guidelight Voyagers are one of the best things about Aetherdrift, Daretti is the best, full stop
Viridian Revel, Disciple of the Vault, Tarrian's Soulcleaver, Pain Distributor, and Sardian Avenger each work with treasures that opponent's use
Not only is the exact placing very subjective but there are a vast number of cards that seem rather hard done by to not be on this list including Sylvan Library, Joraga Treespeaker, Birthing Pod, Rofellos, Natural Order, Wall of Roots, Lotus Cobra and many more
EDIT : A friend pointed out that a sorcery and instant with landfall does exist, so the RNN actually wasnt the first one to experiment with that