Kaza, Roil Chaser This card is more on the not-so-powerful end of things, and it certainly won't single-handedly win you a game
6, Wizards of the Coast published the official decklists for the set's two preconstructed Commander decks, along with a 36-minute video showcasing each deck and explaining the core mechanics of each
Sven Stolz Yawgmoth, Thran Physician is the key card of its own deck GB Yawgmoth and put up decent results in Modern so far
Conjurers Closet and Thassa, Deep-Dwelling will be some of the easiest ways to guarantee Lavinia keeps cheap permanents on lockdown, but having a suite of blink spells to back them up is never going to be a bad thing especially since it wont take long for Lavinia to become a priority removal target for the rest of the table
and if for some reason you decide to later in the game, swinging with him boosts your horde of undead the turn he comes down because he has haste