Your pet cards that were too expensive in previous sets like the wonderful Fairy Godmother, Mystic Armorer or Snow White, Well Wisher will now be a lot easier to shift out if theyre paired with Emerald and this globby little guy
Still, if you have seeded your graveyard with creatures you can cast, once this lands, you can turn your graveyard into your hand, at least for creatures
Cards like Phyrexian Arena are also staples across formats, allowing you to have game against slower decks while slowly burying them in card advantage
Since it has flying, it becomes even harder to block once its stats start increasing
Creatures can't support themselves, which is kind of sad, but it means that if the ability that tells you to support is found on a permanent, the support ability can't target that permanent