Sorcery Color tag templates(None) Cultivate Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle
Nissa, WorldwakerNissa, Worldwaker seems like at least a sidegrade to a creature like Kalonian TwingroveKalonian Twingrove
Souvenir Snatcher As the sole mutate creature in your deck, Souvenir Snatcher steals an artifact and usually buffs a creature at the same time
What Counts as a Fair Trade
Legendary Creature - Shapeshifter Ramp (CTRL to add secondary) Tokens Shelob, Child of Ungoliant Deathtouch, ward Other Spiders you control have deathtouch and ward
The more well-known examples like Blood Moon, or even Back to Basics and Harbinger of the Sea in blue, are all ongoing