Morph is awesome
Or, as another writer dubbed me, Stephen the Sorcerer
A colorless land that you can sacrifice to destroy a non-basic land
We could also consider trying Relentless Dead if we wanted to go for more of a zombie package, perhaps including Cryptbreaker or Stitchers Supplier with some graveyard synergies
If you want still more out of your 3 mana investment, Uro, Titan of Natures Wrath lets you draw a card, gain 3 life, put a land onto the battlefield, and then do it again later in the game for 4 mana and 5 other cards in your graveyard via the Escape mechanic
As for the best of the new creatures, O'aka, Traveling Merchant turns your excess counters into carddraw, and Maester Seymour grows creatures of your choice as you grow him