Another popular card and commander for poison decks is Atraxa, Praetors' Voice because it allows you to proliferate on your every end step
Having a secret entrance behind a bookcase is a classic
If you are relatively new, or are just ripping open booster packs for the first time, you may want to cover all of the rarities of the cards first
If you can get some milling going (see above for what milling means!), you have a side plan of The Master perfectly enabling Reanimator strategies, getting to tap him to put the likes of Razaketh, the Foul Blooded or Hoarding Broodlord onto the battlefield
2/4 stats and Vigilance let it hold off a lot of the more aggressive creatures in Modern well
Because of this, the market values of cards in the set are still in a highly volatile place, with fluctuations in prices happening constantly