Silas allows you to cast artifacts from your graveyard, so if you self-milled a card like Lion's Eye Diamond or Lotus Petal, you can cast them for free from your graveyard
But even needing three mana to bring it to your hand, Lurrus was still too good for Modern, Pioneer, and Legacy, and ate a belated ban
It's the most recurable creature in the deck, so long as you have another Zombie on the battlefield (which is something the deck can easily provide)
Feed the Swarm One of the biggest shifts in Magics color pie over the last few years has been blacks newfound ability to handle enchantments, and Feed the Swarm remains the standard-bearer for this utility
Level Up ultimately rewards incremental progress, synergy stacking, and clever use of resources