In 2005, Saviors of Kamigawa , the final set in the Champions of Kamigawa block, would do a tweak on flip cards making a rare monocolor cycle that started as creatures and flipped into enchantments
They're the first cards experienced players think of when they want their green deck to draw a lot of cards
If your main goal is to make Legacy more affordable and accessible, however, there are other, better, easier ways to do it that dont involve fighting against WotCs seemingly unbreakable oath
Liliana Vess allows the player to force their opponent to discard cards, allows them to search their library for a specific card, and can return all creatures in both player's graveyards to the battlefield under their control, flooding the board with creatures for a huge swing, which will often lead to the end of the game
This means that when paired with a board full of artifacts, Universal Surveillance can be used to draw massive sums of cards